Module plottools.circuits

Electrical circuits.

Axes member functions

• resistance_h(): draw a horizontal resistance.
• resistance_v(): draw a vertical resistance.
• resistance(): draw an arbitrarily rotated resistance.
• capacitance_h(): draw a horizontal capacitance.
• capacitance_v(): draw a vertical capacitance.
• battery_h(): draw a horizontal battery (voltage source).
• battery_v(): draw a vertical battery (voltage source).
• ground(): draw ground.
• opamp_l(): draw an operational amplifier with inputs on the left.
• opamp_l(): draw an operational amplifier with inputs on the right.
• node(): draw a node connecting lines.
• connect(): draw lines directly connecting circuit elements.
• connect_straight(): draw straight lines connecting circuit elements.

Classes

• class Pos: x and y coordinate of a circuit element.

Settings

• circuits_params(): set rc settings for circuits.

matplotlib.rcParams defined by the circuits module:

circuits.scale: 1
circuits.connectwidth: 1
circuits.linewidth: 2
circuits.color: 'black'
circuits.facecolor: 'white'
circuits.alpha: 1
circuits.zorder: 100
circuits.font: dict()

Install/uninstall circuits functions

You usually do not need to call these functions. Upon loading the circuits module, install_circuits() is called automatically.

• install_circuits(): install functions of the circuits module in matplotlib.
• uninstall_circuits(): uninstall all code of the circuits module from matplotlib.

"""
Electrical circuits.

## Axes member functions

- `resistance_h()`: draw a horizontal resistance.
- `resistance_v()`: draw a vertical resistance.
- `resistance()`: draw an arbitrarily rotated resistance.
- `capacitance_h()`: draw a horizontal capacitance.
- `capacitance_v()`: draw a vertical capacitance.
- `battery_h()`: draw a horizontal battery (voltage source).
- `battery_v()`: draw a vertical battery (voltage source).
- `ground()`: draw ground.
- `opamp_l()`: draw an operational amplifier with inputs on the left.
- `opamp_l()`: draw an operational amplifier with inputs on the right.
- `node()`: draw a node connecting lines.
- `connect()`: draw lines directly connecting circuit elements.
- `connect_straight()`: draw straight lines connecting circuit elements.


## Classes

- `class Pos`: x and y coordinate of a circuit element.


## Settings

- `circuits_params()`: set rc settings for circuits.

`matplotlib.rcParams` defined by the circuits module:
```py
circuits.scale: 1
circuits.connectwidth: 1
circuits.linewidth: 2
circuits.color: 'black'
circuits.facecolor: 'white'
circuits.alpha: 1
circuits.zorder: 100
circuits.font: dict()
```


## Install/uninstall circuits functions

You usually do not need to call these functions. Upon loading the circuits
module, `install_circuits()` is called automatically.

- `install_circuits()`: install functions of the circuits module in matplotlib.
- `uninstall_circuits()`: uninstall all code of the circuits module from matplotlib.

"""

import numpy as np
import matplotlib as mpl
import matplotlib.transforms as mpt
import matplotlib.rcsetup as mrc
import matplotlib.pyplot as plt
from matplotlib.patches import Rectangle, Circle, Polygon
from .rcsetup import _validate_fontdict


class Pos(tuple):
    """ x and y coordinate of a circuit element.
    """

    def __new__(cls, x, y):
        return tuple.__new__(cls, (x, y))

    def x(self):
        """ x coordinate of the circuit element.

        Returns
        -------
        x: float
            x-coordinate
        """
        return self[0]

    def y(self):
        """ y coordinate of the circuit element.

        Returns
        -------
        y: float
            y-coordinate
        """
        return self[1]

    def up(self, delta=1):
        """ Increment y coordinate of position of circuit element.

        Parameters
        ----------
        delta: float
            Increment in data coordinates.

        Returns
        -------
        pos: Pos
            Incremented copy of position of circuit element.
        """
        return Pos(self[0], self[1] + delta)

    def down(self, delta=1):
        """ Decrement y coordinate of position of circuit element.

        Parameters
        ----------
        delta: float
            Decrement in data coordinates.

        Returns
        -------
        pos: Pos
            Decremented copy of position of circuit element.
        """
        return Pos(self[0], self[1] - delta)

    def left(self, delta=1):
        """ Decrement x coordinate of position of circuit element.

        Parameters
        ----------
        delta: float
            Decrement in data coordinates.

        Returns
        -------
        pos: Pos
            Decremented copy of position of circuit element.
        """
        return Pos(self[0] - delta, self[1])

    def right(self, delta=1):
        """ Increment x coordinate of position of circuit element.

        Parameters
        ----------
        delta: float
            Increment in data coordinates.

        Returns
        -------
        pos: Pos
            Incremented copy of position of circuit element.
        """
        return Pos(self[0] + delta, self[1])

    def ups(self, delta=1):
        """ Increment y coordinate of position of circuit element.

        Parameters
        ----------
        delta: float
            Increment in multiples of circuits scale (rcParam `circuits.scale`).

        Returns
        -------
        pos: Pos
            Incremented copy of position of circuit element.
        """
        return Pos(self[0], self[1] + delta*mpl.rcParams['circuits.scale'])

    def downs(self, delta=1):
        """ Decrement y coordinate of position of circuit element.

        Parameters
        ----------
        delta: float
            Decrement in multiples of circuits scale (rcParam `circuits.scale`).

        Returns
        -------
        pos: Pos
            Decremented copy of position of circuit element.
        """
        return Pos(self[0], self[1] - delta*mpl.rcParams['circuits.scale'])

    def lefts(self, delta=1):
        """ Decrement x coordinate of position of circuit element.

        Parameters
        ----------
        delta: float
            Decrement in multiples of circuits scale (rcParam `circuits.scale`).

        Returns
        -------
        pos: Pos
            Decremented copy of position of circuit element.
        """
        return Pos(self[0] - delta*mpl.rcParams['circuits.scale'], self[1])

    def rights(self, delta=1):
        """ Increment x coordinate of position of circuit element.

        Parameters
        ----------
        delta: float
            Increment in multiples of circuits scale (rcParam `circuits.scale`).

        Returns
        -------
        pos: Pos
            Incremented copy of position of circuit element.
        """
        return Pos(self[0] + delta*mpl.rcParams['circuits.scale'], self[1])


def resistance_h(ax, pos, label='', align='above', lw=None,
                 color=None, facecolor=None, alpha=None, zorder=None,
                 **kwargs):
    """ Draw a horizontal resistance.

    Parameters
    ----------
    ax: matplotlib axes
        Axes where to draw the resistance bar.
    pos: Pos or 2-tuple of floats
        x and y-coordinate of position of the center of the resistance.
    label: string
        Optional label for the resistance.
    align: 'above', 'below', 'center'
        Position the label above, below or in the center of the resistance.
    lw: float, int
        Linewidth for drawing the outline of the resistance.
        Defaults to `circuits.linewidth` rcParams settings.
    color matplotlib color
        Color for the outline of the resistance.
        Defaults to `circuits.color` rcParams settings.
    facecolor matplotlib color
        Color for filling the resistance.
        Defaults to `circuits.facecolor` rcParams settings.
    alpha: float
        Alpha value for the face color.
        Defaults to `circuits.alpha` rcParams settings.
    zorder: int
        zorder for the resistance and the label.
        Defaults to `circuits.zorder` rcParams settings.
    kwargs: key-word arguments
        Passed on to `ax.text()` used to print the label.
        Defaults to `circuits.font` rcParams settings.

    Returns
    -------
    posl: Pos
        Coordinates of the left end of the resistance.
    posr: Pos
        Coordinates of the right end of the resistance.

    Raises
    ------
    ValueError:
        Invalid value for `align`.
    """
    if lw is None:
        lw = mpl.rcParams['circuits.linewidth']
    if color is None:
        color = mpl.rcParams['circuits.color']
    if facecolor is None:
        facecolor = mpl.rcParams['circuits.facecolor']
    if alpha is None:
        alpha = mpl.rcParams['circuits.alpha']
    if zorder is None:
        zorder = mpl.rcParams['circuits.zorder']
    for k in mpl.rcParams['circuits.font']:
        if not k in kwargs:
            kwargs[k] = mpl.rcParams['circuits.font'][k]
    w = mpl.rcParams['circuits.scale']
    h = 0.5*mpl.rcParams['circuits.scale']
    x, y = pos
    ax.add_patch(Rectangle((x - 0.5*w, y - 0.5*h), w, h,
                           zorder=zorder, edgecolor='none',
                           facecolor=facecolor, alpha=alpha))
    ax.add_patch(Rectangle((x - 0.5*w, y - 0.5*h), w, h,
                           zorder=zorder+1, edgecolor=color,
                           facecolor='none', lw=lw))
    if label:
        ha = 'center'
        va = 'center'
        if align == 'above':
            yy = 0.7*h
            va = 'bottom'
        elif align == 'below':
            yy = -0.7*h
            va = 'top'
        elif align == 'center':
            yy = 0
        else:
            raise ValueError('align must be one of "above", "bottom", or "center"')
        if not 'ha' in kwargs and not 'horizontalalignment' in kwargs:
            kwargs['ha'] = ha
        if not 'va' in kwargs and not 'verticalalignment' in kwargs:
            kwargs['va'] = va
        ax.text(x, y + yy, label, zorder=zorder+1, **kwargs)
    return Pos(x - 0.5*w, y), Pos(x + 0.5*w, y)


def resistance_v(ax, pos, label='', align='right', lw=None, color=None,
                 facecolor=None, alpha=None, zorder=None, **kwargs):
    """ Draw a vertical resistance.

    Parameters
    ----------
    ax: matplotlib axes
        Axes where to draw the resistance.
    pos: Pos or 2-tuple of floats
        x and y-coordinate of position of the center of the resistance.
    label: string
        Optional label for the resistance.
    align: 'left', 'right', 'center'
        Position the label to th left, right or in the center of the resistance.
    lw: float, int
        Linewidth for drawing the outline of the resistance.
        Defaults to `circuits.linewidth` rcParams settings.
    color matplotlib color
        Color for the outline of the resistance.
        Defaults to `circuits.color` rcParams settings.
    facecolor matplotlib color
        Color for filling the resistance.
        Defaults to `circuits.facecolor` rcParams settings.
    alpha: float
        Alpha value for the face color.
        Defaults to `circuits.alpha` rcParams settings.
    zorder: int
        zorder for the resistance and the label.
        Defaults to `circuits.zorder` rcParams settings.
    kwargs: key-word arguments
        Passed on to `ax.text()` used to print the label.
        Defaults to `circuits.font` rcParams settings.

    Returns
    -------
    posb: Pos
        Coordinates of the bottom end of the resistance.
    post: Pos
        Coordinates of the top end of the resistance.

    Raises
    ------
    ValueError:
        Invalid value for `align`.
    """
    if lw is None:
        lw = mpl.rcParams['circuits.linewidth']
    if color is None:
        color = mpl.rcParams['circuits.color']
    if facecolor is None:
        facecolor = mpl.rcParams['circuits.facecolor']
    if alpha is None:
        alpha = mpl.rcParams['circuits.alpha']
    if zorder is None:
        zorder = mpl.rcParams['circuits.zorder']
    for k in mpl.rcParams['circuits.font']:
        if not k in kwargs:
            kwargs[k] = mpl.rcParams['circuits.font'][k]
    w = 0.5*mpl.rcParams['circuits.scale']
    h = mpl.rcParams['circuits.scale']
    x, y = pos
    ax.add_patch(Rectangle((x - 0.5*w, y - 0.5*h), w, h,
                           zorder=zorder, edgecolor='none',
                           facecolor=facecolor, alpha=alpha))
    ax.add_patch(Rectangle((x - 0.5*w, y - 0.5*h), w, h,
                           zorder=zorder+1, edgecolor=color,
                           facecolor='none', lw=lw))
    if label:
        ha = 'center'
        va = 'center'
        if align == 'right':
            xx = 0.7*w
            ha = 'left'
        elif align == 'left':
            xx = -0.7*w
            ha = 'right'
        elif align == 'center':
            xx = 0
        else:
            raise ValueError('align must be one of "left", "right", or "center"')
        if not 'ha' in kwargs and not 'horizontalalignment' in kwargs:
            kwargs['ha'] = ha
        if not 'va' in kwargs and not 'verticalalignment' in kwargs:
            kwargs['va'] = va
        ax.text(x + xx, y, label, zorder=zorder+1, **kwargs)
    return Pos(x, y - 0.5*h), Pos(x, y + 0.5*h)


def resistance(ax, pos, angle=0, label='', align='above', lw=None,
               color=None, facecolor=None, alpha=None, zorder=None,
               **kwargs):
    """Draw an arbitrarily rotated resistance.

    Parameters
    ----------
    ax: matplotlib axes
        Axes where to draw the resistance bar.
    pos: Pos or 2-tuple of floats
        x and y-coordinate of position of the center of the resistance.
    angle: float
        Rotation angle in degrees.
    label: string
        Optional label for the resistance.
    align: 'above', 'below', 'center'
        Position the label above, below or in the center of the
        non-rotated resistance.
    lw: float, int
        Linewidth for drawing the outline of the resistance.
        Defaults to `circuits.linewidth` rcParams settings.
    color matplotlib color
        Color for the outline of the resistance.
        Defaults to `circuits.color` rcParams settings.
    facecolor matplotlib color
        Color for filling the resistance.
        Defaults to `circuits.facecolor` rcParams settings.
    alpha: float
        Alpha value for the face color.
        Defaults to `circuits.alpha` rcParams settings.
    zorder: int
        zorder for the resistance and the label.
        Defaults to `circuits.zorder` rcParams settings.
    kwargs: key-word arguments
        Passed on to `ax.text()` used to print the label.
        Defaults to `circuits.font` rcParams settings.

    Returns
    -------
    posl: Pos
        Coordinates of the left end of the resistance.
    posr: Pos
        Coordinates of the right end of the resistance.

    Raises
    ------
    ValueError:
        Invalid value for `align`.
    """
    if lw is None:
        lw = mpl.rcParams['circuits.linewidth']
    if color is None:
        color = mpl.rcParams['circuits.color']
    if facecolor is None:
        facecolor = mpl.rcParams['circuits.facecolor']
    if alpha is None:
        alpha = mpl.rcParams['circuits.alpha']
    if zorder is None:
        zorder = mpl.rcParams['circuits.zorder']
    for k in mpl.rcParams['circuits.font']:
        if not k in kwargs:
            kwargs[k] = mpl.rcParams['circuits.font'][k]
    w = mpl.rcParams['circuits.scale']
    h = 0.5*mpl.rcParams['circuits.scale']
    x, y = pos
    transform = mpt.Affine2D().rotate(np.radians(angle)).translate(*pos)
    ax.add_patch(Rectangle((-0.5*w, -0.5*h), w, h,
                           transform=transform + ax.transData,
                           zorder=zorder, edgecolor='none',
                           facecolor=facecolor, alpha=alpha))
    ax.add_patch(Rectangle((-0.5*w, -0.5*h), w, h,
                           transform=transform + ax.transData,
                           zorder=zorder+1, edgecolor=color,
                           facecolor='none', lw=lw))
    if label:
        if angle < 0:
            angle += 360
        ha = 'center'
        va = 'center'
        if align == 'above':
            pos = np.array(((0, 0.8*h),))
            if angle > 45 and angle < 45 + 90:
                ha = 'right'
            elif angle > 45 + 180 and angle < 45 + 270:
                ha = 'left'
            if angle > 45 + 270 and angle < 45:
                va = 'bottom'
            elif angle > 45 + 90 and angle < 45 + 180:
                va = 'top'
        elif align == 'below':
            pos = np.array(((0, -0.8*h),))
            if angle > 45 and angle < 45 + 90:
                ha = 'left'
            elif angle > 45 + 180 and angle < 45 + 270:
                ha = 'right'
            if angle > 45 + 270 and angle < 45:
                va = 'top'
            elif angle > 45 + 90 and angle < 45 + 180:
                va = 'bottom'
        elif align == 'center':
            pos = np.array(((0, 0),))
        else:
            raise ValueError('align must be one of "above", "bottom", or "center"')
        pos = transform.transform(pos)
        if not 'ha' in kwargs and not 'horizontalalignment' in kwargs:
            kwargs['ha'] = ha
        if not 'va' in kwargs and not 'verticalalignment' in kwargs:
            kwargs['va'] = va
        ax.text(pos[0,0], pos[0,1], label, zorder=zorder+1, **kwargs)
    nodes = np.array(((-0.5*w, 0), (+0.5*w, 0)))
    nodes = transform.transform(nodes)
    return Pos(*nodes[0,:]),  Pos(*nodes[1,:])


def capacitance_h(ax, pos, label='', align='above', lw=None,
                  color=None, zorder=None, **kwargs):
    """ Draw a horizontal capacitance.

    Parameters
    ----------
    ax: matplotlib axes
        Axes where to draw the capacitance.
    pos: Pos or 2-tuple of floats
        x and y-coordinate of position of the center of the capacitance.
    label: string
        Optional label for the capacitance.
    align: 'above', 'below'
        Position the label above or below the capacitance.
    lw: float, int
        Linewidth for drawing the outline of the capacitance.
        Defaults to `circuits.linewidth` rcParams settings.
    color matplotlib color
        Color for the outline of the capacitance.
        Defaults to `circuits.color` rcParams settings.
    zorder: int
        zorder for the capacitance and the label.
        Defaults to `circuits.zorder` rcParams settings.
    kwargs: key-word arguments
        Passed on to `ax.text()` used to print the label.
        Defaults to `circuits.font` rcParams settings.

    Returns
    -------
    posl: Pos
        Coordinates of the left end of the capacitance.
    posr: Pos
        Coordinates of the right end of the capacitance.

    Raises
    ------
    ValueError:
        Invalid value for `align`.
    """
    if lw is None:
        lw = mpl.rcParams['circuits.linewidth']
    if color is None:
        color = mpl.rcParams['circuits.color']
    if zorder is None:
        zorder = mpl.rcParams['circuits.zorder']
    for k in mpl.rcParams['circuits.font']:
        if not k in kwargs:
            kwargs[k] = mpl.rcParams['circuits.font'][k]
    w = mpl.rcParams['circuits.scale']
    h = mpl.rcParams['circuits.scale']*0.8/3
    x, y = pos
    ax.plot([x - 0.5*h, x - 0.5*h], [y - 0.5*w, y + 0.5*w],
            zorder=zorder, lw=lw, color=color)
    ax.plot([x + 0.5*h, x + 0.5*h], [y - 0.5*w, y + 0.5*w],
            zorder=zorder, lw=lw, color=color)
    if label:
        yy = 0
        ha = 'center'
        va = 'center'
        if align == 'above':
            yy = 0.6*w
            va = 'bottom'
        elif align == 'below':
            yy = -0.6*w
            va = 'top'
        else:
            raise ValueError('align must be one of "above" or "bottom"')
        if not 'ha' in kwargs and not 'horizontalalignment' in kwargs:
            kwargs['ha'] = ha
        if not 'va' in kwargs and not 'verticalalignment' in kwargs:
            kwargs['va'] = va
        ax.text(x, y + yy, label, zorder=zorder, **kwargs)
    return Pos(x - 0.5*h, y), Pos(x + 0.5*h, y)


def capacitance_v(ax, pos, label='', align='right', lw=None,
                  color=None, zorder=None, **kwargs):
    """ Draw a vertical capacitance.

    Parameters
    ----------
    ax: matplotlib axes
        Axes where to draw the capacitance.
    pos: Pos or 2-tuple of floats
        x and y-coordinate of position of the center of the capacitance.
    label: string
        Optional label for the capacitance.
    align: 'left', 'right'
        Position the label to the left or to the right of the capacitance.
    lw: float, int
        Linewidth for drawing the outline of the capacitance.
        Defaults to `circuits.linewidth` rcParams settings.
    color matplotlib color
        Color for the outline of the capacitance.
        Defaults to `circuits.color` rcParams settings.
    zorder: int
        zorder for the capacitance and the label.
        Defaults to `circuits.zorder` rcParams settings.
    kwargs: key-word arguments
        Passed on to `ax.text()` used to print the label.
        Defaults to `circuits.font` rcParams settings.

    Returns
    -------
    posb: Pos
        Coordinates of the bottom end of the capacitance.
    post: Pos
        Coordinates of the top end of the capacitance.

    Raises
    ------
    ValueError:
        Invalid value for `align`.
    """
    if lw is None:
        lw = mpl.rcParams['circuits.linewidth']
    if color is None:
        color = mpl.rcParams['circuits.color']
    if zorder is None:
        zorder = mpl.rcParams['circuits.zorder']
    for k in mpl.rcParams['circuits.font']:
        if not k in kwargs:
            kwargs[k] = mpl.rcParams['circuits.font'][k]
    w = mpl.rcParams['circuits.scale']
    h = mpl.rcParams['circuits.scale']*0.8/3
    x, y = pos
    ax.plot([x - 0.5*w, x + 0.5*w], [y + 0.5*h, y + 0.5*h],
            zorder=zorder, lw=lw, color=color)
    ax.plot([x - 0.5*w, x + 0.5*w], [y - 0.5*h, y - 0.5*h],
            zorder=zorder, lw=lw, color=color)
    if label:
        ha = 'center'
        va = 'center'
        if align == 'right':
            xx = 0.6*w
            ha = 'left'
        elif align == 'left':
            xx = -0.6*w
            ha = 'right'
        else:
            raise ValueError('align must be one of "left" or "right"')
        if not 'ha' in kwargs and not 'horizontalalignment' in kwargs:
            kwargs['ha'] = ha
        if not 'va' in kwargs and not 'verticalalignment' in kwargs:
            kwargs['va'] = va
        ax.text(x + xx, y, label, zorder=zorder, **kwargs)
    return Pos(x, y - 0.5*h), Pos(x, y + 0.5*h)


def battery_h(ax, pos, label='', align='above', lw=None, color=None,
              zorder=None, **kwargs):
    """ Draw a horizontal battery (voltage source).

    Parameters
    ----------
    ax: matplotlib axes
        Axes where to draw the battery.
    pos: Pos or 2-tuple of floats
        x and y-coordinate of position of the center of the battery.
    label: string
        Optional label for the battery.
    align: 'above', 'below'
        Position the label above or below the battery.
    lw: float, int
        Linewidth for drawing the outline of the battery.
        Defaults to `circuits.linewidth` rcParams settings.
    color matplotlib color
        Color for the outline of the battery.
        Defaults to `circuits.color` rcParams settings.
    zorder: int
        zorder for the battery and the label.
        Defaults to `circuits.zorder` rcParams settings.
    kwargs: key-word arguments
        Passed on to `ax.text()` used to print the label.
        Defaults to `circuits.font` rcParams settings.

    Returns
    -------
    posl: Pos
        Coordinates of the left end of the battery.
    posr: Pos
        Coordinates of the right end of the battery.

    Raises
    ------
    ValueError:
        Invalid value for `align`.
    """
    if lw is None:
        lw = mpl.rcParams['circuits.linewidth']
    if color is None:
        color = mpl.rcParams['circuits.color']
    if zorder is None:
        zorder = mpl.rcParams['circuits.zorder']
    for k in mpl.rcParams['circuits.font']:
        if not k in kwargs:
            kwargs[k] = mpl.rcParams['circuits.font'][k]
    w = mpl.rcParams['circuits.scale']*4/3
    h = mpl.rcParams['circuits.scale']*0.8/3
    x, y = pos
    ax.plot([x - 0.5*h, x - 0.5*h], [y - 0.5*w, y + 0.5*w],
            zorder=zorder, lw=lw, color=color)
    ax.plot([x + 0.5*h, x + 0.5*h], [y - 0.25*w, y + 0.25*w],
            zorder=zorder, lw=lw, color=color)
    if label:
        yy = 0
        ha = 'center'
        va = 'center'
        if align == 'above':
            yy = 0.6*w
            va = 'bottom'
        elif align == 'below':
            yy = -0.6*w
            va = 'top'
        else:
            raise ValueError('align must be one of "above" or "bottom"')
        if not 'ha' in kwargs and not 'horizontalalignment' in kwargs:
            kwargs['ha'] = ha
        if not 'va' in kwargs and not 'verticalalignment' in kwargs:
            kwargs['va'] = va
        ax.text(x, y + yy, label, zorder=zorder, **kwargs)
    return Pos(x - 0.5*h, y), Pos(x + 0.5*h, y)


def battery_v(ax, pos, label='', align='right', lw=None, color=None,
              zorder=None, **kwargs):
    """ Draw a vertical battery (voltage source).

    Parameters
    ----------
    ax: matplotlib axes
        Axes where to draw the battery.
    pos: Pos or 2-tuple of floats
        x and y-coordinate of position of the center of the battery.
    label: string
        Optional label for the battery.
    align: 'left', 'right'
        Position the label to the left or to the right of the battery.
    lw: float, int
        Linewidth for drawing the outline of the battery.
        Defaults to `circuits.linewidth` rcParams settings.
    color matplotlib color
        Color for the outline of the battery.
        Defaults to `circuits.color` rcParams settings.
    zorder: int
        zorder for the battery and the label.
        Defaults to `circuits.zorder` rcParams settings.
    kwargs: key-word arguments
        Passed on to `ax.text()` used to print the label.
        Defaults to `circuits.font` rcParams settings.

    Returns
    -------
    posb: Pos
        Coordinates of the bottom end of the battery.
    post: Pos
        Coordinates of the top end of the battery.

    Raises
    ------
    ValueError:
        Invalid value for `align`.
    """
    if lw is None:
        lw = mpl.rcParams['circuits.linewidth']
    if color is None:
        color = mpl.rcParams['circuits.color']
    if zorder is None:
        zorder = mpl.rcParams['circuits.zorder']
    for k in mpl.rcParams['circuits.font']:
        if not k in kwargs:
            kwargs[k] = mpl.rcParams['circuits.font'][k]
    w = mpl.rcParams['circuits.scale']*4/3
    h = mpl.rcParams['circuits.scale']*0.8/3
    x, y = pos
    ax.plot([x - 0.5*w, x + 0.5*w], [y + 0.5*h, y + 0.5*h],
            zorder=zorder, lw=lw, color=color)
    ax.plot([x - 0.25*w, x + 0.25*w], [y - 0.5*h, y - 0.5*h],
            zorder=zorder, lw=lw, color=color)
    if label:
        ha = 'center'
        va = 'center'
        if align == 'right':
            xx = 0.6*w
            ha = 'left'
        elif align == 'left':
            xx = -0.6*w
            ha = 'right'
        else:
            raise ValueError('align must be one of "left" or "right"')
        if not 'ha' in kwargs and not 'horizontalalignment' in kwargs:
            kwargs['ha'] = ha
        if not 'va' in kwargs and not 'verticalalignment' in kwargs:
            kwargs['va'] = va
        ax.text(x + xx, y, label, zorder=zorder, **kwargs)
    return Pos(x, y - 0.5*h), Pos(x, y + 0.5*h)


def ground(ax, pos, label='', align='right', lw=None, color=None,
           zorder=None, **kwargs):
    """ Draw ground.

    Parameters
    ----------
    ax: matplotlib axes
        Axes where to draw the battery.
    pos: Pos or 2-tuple of floats
        x and y-coordinate of position of the center of the battery.
    label: string
        Optional label for the battery.
    align: 'left', 'right'
        Position the label to the left or to the right of the ground.
    lw: float, int
        Linewidth for drawing the outline of the battery.
        Defaults to `circuits.linewidth` rcParams settings.
    color matplotlib color
        Color for the outline of the battery.
        Defaults to `circuits.color` rcParams settings.
    zorder: int
        zorder for the battery and the label.
        Defaults to `circuits.zorder` rcParams settings.
    kwargs: key-word arguments
        Passed on to `ax.text()` used to print the label.
        Defaults to `circuits.font` rcParams settings.

    Returns
    -------
    pos: Pos
        Coordinates of the top end of ground.

    Raises
    ------
    ValueError:
        Invalid value for `align`.
    """
    if lw is None:
        lw = mpl.rcParams['circuits.linewidth']
    if color is None:
        color = mpl.rcParams['circuits.color']
    if zorder is None:
        zorder = mpl.rcParams['circuits.zorder']
    for k in mpl.rcParams['circuits.font']:
        if not k in kwargs:
            kwargs[k] = mpl.rcParams['circuits.font'][k]
    w = mpl.rcParams['circuits.scale']*0.8
    h = mpl.rcParams['circuits.scale']*0.17
    x, y = pos
    ax.plot([x - 0.5*w, x + 0.5*w], [y + h, y + h],
            zorder=zorder, lw=lw, color=color)
    ax.plot([x - 0.3*w, x + 0.3*w], [y, y],
            zorder=zorder, lw=lw, color=color)
    ax.plot([x - 0.06*w, x + 0.06*w], [y - h, y - h],
            zorder=zorder, lw=lw, color=color)
    if label:
        ha = 'center'
        va = 'center'
        if align == 'right':
            xx = 0.7*w
            ha = 'left'
        elif align == 'left':
            xx = -0.7*w
            ha = 'right'
        else:
            raise ValueError('align must be one of "left" or "right"')
        if not 'ha' in kwargs and not 'horizontalalignment' in kwargs:
            kwargs['ha'] = ha
        if not 'va' in kwargs and not 'verticalalignment' in kwargs:
            kwargs['va'] = va
        ax.text(x + xx, y, label, zorder=zorder, **kwargs)
    return Pos(x, y + h)


def opamp_l(ax, pos, label='', align='above', lw=None, color=None,
            facecolor=None, alpha=None, zorder=None, **kwargs):
    """ Draw an operational amplifier with inputs on the left.

    Parameters
    ----------
    ax: matplotlib axes
        Axes where to draw the opamp.
    pos: Pos or 2-tuple of floats
        x and y-coordinate of position of the center of the opamp.
    label: string
        Optional label for the opamp.
    align: 'above', 'below', 'center'
        Position the label above, below or in the center of the opamp.
    lw: float, int
        Linewidth for drawing the outline of the opamp.
        Defaults to `circuits.linewidth` rcParams settings.
    color matplotlib color
        Color for the outline of the opamp.
        Defaults to `circuits.color` rcParams settings.
    facecolor matplotlib color
        Color for filling the opamp.
        Defaults to `circuits.facecolor` rcParams settings.
    alpha: float
        Alpha value for the face color.
        Defaults to `circuits.alpha` rcParams settings.
    zorder: int
        zorder for the opamp and the label.
        Defaults to `circuits.zorder` rcParams settings.
    kwargs: key-word arguments
        Passed on to `ax.text()` used to print the label.
        Defaults to `circuits.font` rcParams settings.

    Returns
    -------
    pospos: Pos
        Coordinates of the positive (upper) input of the opamp.
    posneg: Pos
        Coordinates of the negative (lower) input of the opamp.
    posout: Pos
        Coordinates of the output of the opamp.
    posgnd: Pos
        Coordinates of the ground supply of the opamp.

    Raises
    ------
    ValueError:
        Invalid value for `align`.
    """
    if lw is None:
        lw = mpl.rcParams['circuits.linewidth']
    if color is None:
        color = mpl.rcParams['circuits.color']
    if facecolor is None:
        facecolor = mpl.rcParams['circuits.facecolor']
    if alpha is None:
        alpha = mpl.rcParams['circuits.alpha']
    if zorder is None:
        zorder = mpl.rcParams['circuits.zorder']
    for k in mpl.rcParams['circuits.font']:
        if not k in kwargs:
            kwargs[k] = mpl.rcParams['circuits.font'][k]
    a = mpl.rcParams['circuits.scale']*5/3
    r = a/2/np.sqrt(3)
    x, y = pos
    xy = np.array([[x - r, y - 0.5*a], [x - r, y + 0.5*a], [x + 2*r, y]])
    ax.add_patch(Polygon(xy, closed=True,
                         zorder=zorder, edgecolor='none',
                         facecolor=facecolor, alpha=alpha))
    ax.add_patch(Polygon(xy, closed=True,
                         zorder=zorder+1, edgecolor=color,
                         facecolor='none', lw=lw))
    ax.text(x - 0.8*r, y + 0.21*a, '$+$', ha='left', va='center',
            fontsize='x-small', color=color, zorder=zorder+1)
    ax.text(x - 0.8*r, y - 0.19*a, '$-$', ha='left', va='center',
            fontsize='x-small', color=color, zorder=zorder+1)
    if label:
        ha = 'left'
        va = 'center'
        if align == 'above':
            yy = 1.4*r
            va = 'bottom'
        elif align == 'below':
            yy = -1.4*r
            va = 'top'
        elif align == 'center':
            yy = 0
        else:
            raise ValueError('align must be one of "above", "bottom", or "center"')
        if not 'ha' in kwargs and not 'horizontalalignment' in kwargs:
            kwargs['ha'] = ha
        if not 'va' in kwargs and not 'verticalalignment' in kwargs:
            kwargs['va'] = va
        ax.text(x, y + yy, label, zorder=zorder+1, **kwargs)
    return Pos(x - r, y - 0.2*a), Pos(x - r, y + 0.2*a), Pos(x + 2*r, y), Pos(x, y-1.2*r)


def opamp_r(ax, pos, label='', align='above', lw=None, color=None,
            facecolor=None, alpha=None, zorder=None, **kwargs):
    """ Draw an operational amplifier with inputs on the right.

    Parameters
    ----------
    ax: matplotlib axes
        Axes where to draw the opamp.
    pos: Pos or 2-tuple of floats
        x and y-coordinate of position of the center of the opamp.
    label: string
        Optional label for the opamp.
    align: 'above', 'below', 'center'
        Position the label above, below or in the center of the opamp.
    lw: float, int
        Linewidth for drawing the outline of the opamp.
        Defaults to `circuits.linewidth` rcParams settings.
    color matplotlib color
        Color for the outline of the opamp.
        Defaults to `circuits.color` rcParams settings.
    facecolor matplotlib color
        Color for filling the opamp.
        Defaults to `circuits.facecolor` rcParams settings.
    alpha: float
        Alpha value for the face color.
        Defaults to `circuits.alpha` rcParams settings.
    zorder: int
        zorder for the opamp and the label.
        Defaults to `circuits.zorder` rcParams settings.
    kwargs: key-word arguments
        Passed on to `ax.text()` used to print the label.
        Defaults to `circuits.font` rcParams settings.

    Returns
    -------
    pospos: Pos
        Coordinates of the positive (upper) input of the opamp.
    posneg: Pos
        Coordinates of the negative (lower) input of the opamp.
    posout: Pos
        Coordinates of the output of the opamp.
    posgnd: Pos
        Coordinates of the ground supply of the opamp.

    Raises
    ------
    ValueError:
        Invalid value for `align`.
    """
    if lw is None:
        lw = mpl.rcParams['circuits.linewidth']
    if color is None:
        color = mpl.rcParams['circuits.color']
    if facecolor is None:
        facecolor = mpl.rcParams['circuits.facecolor']
    if alpha is None:
        alpha = mpl.rcParams['circuits.alpha']
    if zorder is None:
        zorder = mpl.rcParams['circuits.zorder']
    for k in mpl.rcParams['circuits.font']:
        if not k in kwargs:
            kwargs[k] = mpl.rcParams['circuits.font'][k]
    a = mpl.rcParams['circuits.scale']*5/3
    r = a/2/np.sqrt(3)
    x, y = pos
    xy = np.array([[x + r, y - 0.5*a], [x + r, y + 0.5*a], [x - 2*r, y]])
    ax.add_patch(Polygon(xy, closed=True,
                         zorder=zorder, edgecolor='none',
                         facecolor=facecolor, alpha=alpha))
    ax.add_patch(Polygon(xy, closed=True,
                         zorder=zorder+1, edgecolor=color,
                         facecolor='none', lw=lw))
    ax.text(x + 0.8*r, y + 0.21*a, '$+$', ha='right', va='center',
            fontsize='x-small', color=color, zorder=zorder+1)
    ax.text(x + 0.8*r, y - 0.19*a, '$-$', ha='right', va='center',
            fontsize='x-small', color=color, zorder=zorder+1)
    if label:
        ha = 'right'
        va = 'center'
        if align == 'above':
            yy = 1.4*r
            va = 'bottom'
        elif align == 'below':
            yy = -1.4*r
            va = 'top'
        elif align == 'center':
            yy = 0
        else:
            raise ValueError('align must be one of "above", "bottom", or "center"')
        if not 'ha' in kwargs and not 'horizontalalignment' in kwargs:
            kwargs['ha'] = ha
        if not 'va' in kwargs and not 'verticalalignment' in kwargs:
            kwargs['va'] = va
        ax.text(x, y + yy, label, zorder=zorder+1, **kwargs)
    return Pos(x + r, y - 0.2*a), Pos(x + r, y + 0.2*a), Pos(x - 2*r, y), Pos(x, y-1.2*r)


def node(ax, pos, label='', align='northeast', color=None,
         zorder=None, **kwargs):
    """ Draw a node connecting lines.

    Parameters
    ----------
    ax: matplotlib axes
        Axes where to draw the node.
    pos: Pos or 2-tuple of floats
        x and y-coordinate of position of the center of the node.
    label: string
        Optional label for the node.
    align: 'left', 'right', 'above', 'below', 'north', 'south', 'west', 'east', 'northwest', 'northeast', 'southwest', 'southeast'
        Position of the label relative to the node.
    color matplotlib color
        Color of the node.
        Defaults to `circuits.color` rcParams settings.
    zorder: int
        zorder for the node.
        Defaults to `circuits.zorder` rcParams settings.
    kwargs: key-word arguments
        Passed on to `ax.text()` used to print the label.
        Defaults to `circuits.font` rcParams settings.

    Returns
    -------
    pos: Pos
        Coordinates of the node.
    """
    if color is None:
        color = mpl.rcParams['circuits.color']
    if zorder is None:
        zorder = mpl.rcParams['circuits.zorder']
    for k in mpl.rcParams['circuits.font']:
        if not k in kwargs:
            kwargs[k] = mpl.rcParams['circuits.font'][k]
    r = mpl.rcParams['circuits.scale']*0.25/3
    ax.add_patch(Circle(pos, r, zorder=zorder, edgecolor='none',
                        facecolor=color))
    if label:
        xx = 0
        yy = 0
        ha = 'center'
        va = 'center'
        if align == 'right' or 'east' in align:
            xx = 2*r
            ha = 'left'
        elif align == 'left' or 'west' in align:
            xx = -2*r
            ha = 'right'
        if align == 'above' or 'north' in align:
            yy = 2*r
            va = 'bottom'
        elif align == 'below' or 'south' in align:
            yy = -2*r
            va = 'top'
        if not 'ha' in kwargs and not 'horizontalalignment' in kwargs:
            kwargs['ha'] = ha
        if not 'va' in kwargs and not 'verticalalignment' in kwargs:
            kwargs['va'] = va
        ax.text(pos[0] + xx, pos[1] + yy, label, zorder=zorder+1, **kwargs)
    return Pos(pos[0], pos[1])


def connect(ax, nodes, lw=None, color=None, zorder=None):
    """ Draw horizontal and vertical lines connecting circuit elements.

    Parameters
    ----------
    ax: matplotlib axes
        Axes where to draw the connections.
    nodes: list of Pos or 2-tuple of floats
        x and y-coordinates of positions that should be connected.
        If an element is `None` then leave a gap between the neighboring nodes.
        Makes only horizontal and vertical connection lines in
        counter-clockwise direction.
    lw: float, int
        Linewidth for drawing the connection lines.
        Defaults to `circuits.linewidth` rcParams settings.
    color matplotlib color
        Color of the connection lines.
        Defaults to `circuits.color` rcParams settings.
    zorder: int
        zorder for the connection lines.
        Defaults to `circuits.zorder` rcParams settings.
    """
    if lw is None:
        lw = mpl.rcParams['circuits.connectwidth']
    if color is None:
        color = mpl.rcParams['circuits.color']
    if zorder is None:
        zorder = mpl.rcParams['circuits.zorder']
    xs = []
    ys = []
    px = None
    py = None
    for n in nodes:
        if n is None:
            xs.append(np.nan)
            ys.append(np.nan)
            px = None
            py = None
        else:
            x = n[0]
            y = n[1]
            if px is None or x == px or y == py:
                xs.append(x)
                ys.append(y)
            else:
                if (x - px)*(y - py) > 0:
                    xs.extend((x, x))
                    ys.extend((py, y))
                else:
                    xs.extend((px, x))
                    ys.extend((y, y))
            px = x
            py = y
    ax.plot(xs, ys, lw=lw, color=color, zorder=zorder)


def connect_straight(ax, nodes, lw=None, color=None, zorder=None):
    """ Draw straight lines connecting circuit elements.

    Parameters
    ----------
    ax: matplotlib axes
        Axes where to draw the connections.
    nodes: list of Pos or 2-tuple of floats
        x and y-coordinates of positions that should be connected.
        If an element is `None` then leave a gap between the neighboring nodes.
    lw: float, int
        Linewidth for drawing the connection lines.
        Defaults to `circuits.linewidth` rcParams settings.
    color matplotlib color
        Color of the connection lines.
        Defaults to `circuits.color` rcParams settings.
    zorder: int
        zorder for the connection lines.
        Defaults to `circuits.zorder` rcParams settings.
    """
    if lw is None:
        lw = mpl.rcParams['circuits.connectwidth']
    if color is None:
        color = mpl.rcParams['circuits.color']
    if zorder is None:
        zorder = mpl.rcParams['circuits.zorder']
    xs = []
    ys = []
    for n in nodes:
        if n is None:
            xs.append(np.nan)
            ys.append(np.nan)
        else:
            x = n[0]
            y = n[1]
            xs.append(x)
            ys.append(y)
    ax.plot(xs, ys, lw=lw, color=color, zorder=zorder)


def circuits_params(scale=None, connectwidth=None, linewidth=None,
                    color=None, facecolor=None, alpha=None,
                    zorder=None, font=None):
    """Set rc settings for circuits.
                  
    Only parameters that are not `None` are updated.

    Parameters
    ----------
    scale: float
        Size of circuit elements as the height of a vertical resistance
        in x/y coordinate units.
    connectwidth: int, float
        Line width of lines connecting circuit elements.
        Set rcParam `circuits.connectwidth`.
    linewidth: int, float
        Line width used for drawing circuit elements.
        Set rcParam `circuits.linewidth`.
    color: matplotlib color
        Color of the connections and circuit elements.
        Set rcParam `circuits.color`.
    facecolor: matplotlib color
        Face color for closed circuit elements like resistances or opamps.
        Set rcParam `circuits.facecolor`.
    alpha: float
        Alpha value for face color for closed circuit elements like
        resistances or opamps.
        Set rcParam `circuits.alpha`.
    zorder: int
        Zorder for all circuit elements drawn.
        Set rcParam `circuits.zorder`.
    font: dict
        Dictionary with font settings used for labeling circuit elements
        (e.g. fontsize, fontfamiliy, fontstyle, fontweight, bbox, ...).
         Set rcParam `circuits.font`.
    """
    if scale is not None and 'circuits.scale' in mrc._validators:
        mpl.rcParams['circuits.scale'] = scale
    if connectwidth is not None and 'circuits.connectwidth' in mrc._validators:
        mpl.rcParams['circuits.connectwidth'] = connectwidth
    if linewidth is not None and 'circuits.linewidth' in mrc._validators:
        mpl.rcParams['circuits.linewidth'] = linewidth
    if color is not None and 'circuits.color' in mrc._validators:
        mpl.rcParams['circuits.color'] = color
    if facecolor is not None and 'circuits.facecolor' in mrc._validators:
        mpl.rcParams['circuits.facecolor'] = facecolor
    if alpha is not None and 'circuits.alpha' in mrc._validators:
        mpl.rcParams['circuits.alpha'] = alpha
    if zorder is not None and 'circuits.zorder' in mrc._validators:
        mpl.rcParams['circuits.zorder'] = zorder
    if font is not None and 'circuits.font' in mrc._validators:
        mpl.rcParams.update({'circuits.font': font})


def install_circuits():
    """ Install circuits functions on matplotlib axes.

    This function is also called automatically upon importing the module.

    See also
    --------
    uninstall_circuits()
    """
    if not hasattr(mpl.axes.Axes, 'resistance_h'):
        mpl.axes.Axes.resistance_h = resistance_h
    if not hasattr(mpl.axes.Axes, 'resistance_v'):
        mpl.axes.Axes.resistance_v = resistance_v
    if not hasattr(mpl.axes.Axes, 'resistance'):
        mpl.axes.Axes.resistance = resistance
    if not hasattr(mpl.axes.Axes, 'capacitance_h'):
        mpl.axes.Axes.capacitance_h = capacitance_h
    if not hasattr(mpl.axes.Axes, 'capacitance_v'):
        mpl.axes.Axes.capacitance_v = capacitance_v
    if not hasattr(mpl.axes.Axes, 'battery_h'):
        mpl.axes.Axes.battery_h = battery_h
    if not hasattr(mpl.axes.Axes, 'battery_v'):
        mpl.axes.Axes.battery_v = battery_v
    if not hasattr(mpl.axes.Axes, 'ground'):
        mpl.axes.Axes.ground = ground
    if not hasattr(mpl.axes.Axes, 'opamp_l'):
        mpl.axes.Axes.opamp_l = opamp_l
    if not hasattr(mpl.axes.Axes, 'opamp_r'):
        mpl.axes.Axes.opamp_r = opamp_r
    if not hasattr(mpl.axes.Axes, 'node'):
        mpl.axes.Axes.node = node
    if not hasattr(mpl.axes.Axes, 'connect'):
        mpl.axes.Axes.connect = connect
    if not hasattr(mpl.axes.Axes, 'connect_straight'):
        mpl.axes.Axes.connect_straight = connect_straight
    # add circuits parameter to rc configuration:
    if 'circuits.scale' not in mpl.rcParams:
        mrc._validators['circuits.scale'] = mrc.validate_float
        mrc._validators['circuits.connectwidth'] = mrc.validate_float
        mrc._validators['circuits.linewidth'] = mrc.validate_float
        mrc._validators['circuits.color'] = mrc.validate_string
        mrc._validators['circuits.facecolor'] = mrc.validate_string
        mrc._validators['circuits.alpha'] = mrc.validate_float
        mrc._validators['circuits.zorder'] = mrc.validate_float
        mrc._validators['circuits.font'] = _validate_fontdict
        mpl.rcParams.update({'circuits.scale': 1,
                             'circuits.connectwidth': 1,
                             'circuits.linewidth': 2,
                             'circuits.color': 'black',
                             'circuits.facecolor': 'white',
                             'circuits.alpha': 1,
                             'circuits.zorder': 100,
                             'circuits.font': dict()})

        
def uninstall_circuits():
    """ Uninstall circuits functions from matplotlib axes.

    Call this code to disable anything that was installed by `install_circuits()`.

    See also
    --------
    install_circuits()
    """
    if hasattr(mpl.axes.Axes, 'resistance_h'):
        delattr(mpl.axes.Axes, 'resistance_h')
    if hasattr(mpl.axes.Axes, 'resistance_v'):
        delattr(mpl.axes.Axes, 'resistance_v')
    if hasattr(mpl.axes.Axes, 'resistance'):
        delattr(mpl.axes.Axes, 'resistance')
    if hasattr(mpl.axes.Axes, 'capacitance_h'):
        delattr(mpl.axes.Axes, 'capacitance_h')
    if hasattr(mpl.axes.Axes, 'capacitance_v'):
        delattr(mpl.axes.Axes, 'capacitance_v')
    if hasattr(mpl.axes.Axes, 'battery_h'):
        delattr(mpl.axes.Axes, 'battery_h')
    if hasattr(mpl.axes.Axes, 'battery_v'):
        delattr(mpl.axes.Axes, 'battery_v')
    if hasattr(mpl.axes.Axes, 'ground'):
        delattr(mpl.axes.Axes, 'ground')
    if hasattr(mpl.axes.Axes, 'opamp_l'):
        delattr(mpl.axes.Axes, 'opamp_l')
    if hasattr(mpl.axes.Axes, 'opamp_r'):
        delattr(mpl.axes.Axes, 'opamp_r')
    if hasattr(mpl.axes.Axes, 'node'):
        delattr(mpl.axes.Axes, 'node')
    if hasattr(mpl.axes.Axes, 'connect'):
        delattr(mpl.axes.Axes, 'connect')
    if hasattr(mpl.axes.Axes, 'connect_straight'):
        delattr(mpl.axes.Axes, 'connect_straight')
    mrc._validators.pop('circuits.scale', None)
    mrc._validators.pop('circuits.connectwidth', None)
    mrc._validators.pop('circuits.linewidth', None)
    mrc._validators.pop('circuits.color', None)
    mrc._validators.pop('circuits.facecolor', None)
    mrc._validators.pop('circuits.alpha', None)
    mrc._validators.pop('circuits.zorder', None)
    mrc._validators.pop('circuits.font', None)


install_circuits()
            
    
def demo():
    fig, ax = plt.subplots()
    e1b, e1t = ax.battery_v((0, 1), r'$E_1$')
    r1b, r1t = ax.resistance_v((e1t[0], 3), r'$R_1$')
    c1b, c1t = ax.capacitance_v((-2, 2), r'$C_1$')
    ax.connect((e1t, r1b, None, r1t, r1t.ups(0.5), c1t, None,
                c1b, e1b.downs(0.5), e1b))
    e2l, e2r = ax.battery_h((0, -1), r'$E_2$', 'below')
    r2l, r2r = ax.resistance_h((-2, e2l.y()), r'$R_2$', 'below')
    c2l, c2r = ax.capacitance_h((-1, -3), r'$C_2$', 'below')
    ax.connect((e2l, r2r, None, r2l, r2l.lefts(0.5), c2l, None,
                c2r, e2r.rights(0.5), e2r))
    op1n, op1p, op1o, op1g = ax.opamp_l((4, 2), r'$OP1$')
    n1n = ax.node(op1n.lefts(2))
    n1p = ax.node(op1p.lefts(2))
    n1o = ax.node(op1o.rights(1))
    gnd1 = ax.ground(op1g.downs(1), r'$GND_1$')
    ax.connect((op1n, n1n))
    ax.connect((op1p, n1p))
    ax.connect((op1o, n1o))
    ax.connect((op1g, gnd1))
    op2n, op2p, op2o, op2g = ax.opamp_r((4, -2), r'$OP2$')
    n2n = ax.node(op2n.rights(1))
    n2p = ax.node(op2p.rights(1))
    n2o = ax.node(op2o.lefts(2))
    gnd2 = ax.ground(op2g.downs(1), r'$GND_2$', 'left')
    ax.connect((op2n, n2n))
    ax.connect((op2p, n2p))
    ax.connect((op2o, n2o))
    ax.connect((op2g, gnd2))
    ax.set_aspect('equal')
    plt.show()


if __name__ == "__main__":
    demo()

Functions

def resistance_h(ax, pos, label='', align='above', lw=None, color=None, facecolor=None, alpha=None, zorder=None, **kwargs)

Draw a horizontal resistance.

Parameters

ax : matplotlib axes

Axes where to draw the resistance bar.

pos : Pos or 2-tuple of floats

x and y-coordinate of position of the center of the resistance.

label : string

Optional label for the resistance.

align : 'above', 'below', 'center'

Position the label above, below or in the center of the resistance.

lw : float, int

Linewidth for drawing the outline of the resistance. Defaults to circuits.linewidth rcParams settings.

color matplotlib color

Color for the outline of the resistance.

Defaults to circuits.color rcParams settings.

facecolor matplotlib color

Color for filling the resistance.

Defaults to circuits.facecolor rcParams settings.

alpha : float

Alpha value for the face color. Defaults to circuits.alpha rcParams settings.

zorder : int

zorder for the resistance and the label. Defaults to circuits.zorder rcParams settings.

kwargs : key-word arguments

Passed on to ax.text() used to print the label. Defaults to circuits.font rcParams settings.

Returns

posl : Pos

Coordinates of the left end of the resistance.

posr : Pos

Coordinates of the right end of the resistance.

Raises

Valueerror

Invalid value for align.

Expand source code

def resistance_h(ax, pos, label='', align='above', lw=None,
                 color=None, facecolor=None, alpha=None, zorder=None,
                 **kwargs):
    """ Draw a horizontal resistance.

    Parameters
    ----------
    ax: matplotlib axes
        Axes where to draw the resistance bar.
    pos: Pos or 2-tuple of floats
        x and y-coordinate of position of the center of the resistance.
    label: string
        Optional label for the resistance.
    align: 'above', 'below', 'center'
        Position the label above, below or in the center of the resistance.
    lw: float, int
        Linewidth for drawing the outline of the resistance.
        Defaults to `circuits.linewidth` rcParams settings.
    color matplotlib color
        Color for the outline of the resistance.
        Defaults to `circuits.color` rcParams settings.
    facecolor matplotlib color
        Color for filling the resistance.
        Defaults to `circuits.facecolor` rcParams settings.
    alpha: float
        Alpha value for the face color.
        Defaults to `circuits.alpha` rcParams settings.
    zorder: int
        zorder for the resistance and the label.
        Defaults to `circuits.zorder` rcParams settings.
    kwargs: key-word arguments
        Passed on to `ax.text()` used to print the label.
        Defaults to `circuits.font` rcParams settings.

    Returns
    -------
    posl: Pos
        Coordinates of the left end of the resistance.
    posr: Pos
        Coordinates of the right end of the resistance.

    Raises
    ------
    ValueError:
        Invalid value for `align`.
    """
    if lw is None:
        lw = mpl.rcParams['circuits.linewidth']
    if color is None:
        color = mpl.rcParams['circuits.color']
    if facecolor is None:
        facecolor = mpl.rcParams['circuits.facecolor']
    if alpha is None:
        alpha = mpl.rcParams['circuits.alpha']
    if zorder is None:
        zorder = mpl.rcParams['circuits.zorder']
    for k in mpl.rcParams['circuits.font']:
        if not k in kwargs:
            kwargs[k] = mpl.rcParams['circuits.font'][k]
    w = mpl.rcParams['circuits.scale']
    h = 0.5*mpl.rcParams['circuits.scale']
    x, y = pos
    ax.add_patch(Rectangle((x - 0.5*w, y - 0.5*h), w, h,
                           zorder=zorder, edgecolor='none',
                           facecolor=facecolor, alpha=alpha))
    ax.add_patch(Rectangle((x - 0.5*w, y - 0.5*h), w, h,
                           zorder=zorder+1, edgecolor=color,
                           facecolor='none', lw=lw))
    if label:
        ha = 'center'
        va = 'center'
        if align == 'above':
            yy = 0.7*h
            va = 'bottom'
        elif align == 'below':
            yy = -0.7*h
            va = 'top'
        elif align == 'center':
            yy = 0
        else:
            raise ValueError('align must be one of "above", "bottom", or "center"')
        if not 'ha' in kwargs and not 'horizontalalignment' in kwargs:
            kwargs['ha'] = ha
        if not 'va' in kwargs and not 'verticalalignment' in kwargs:
            kwargs['va'] = va
        ax.text(x, y + yy, label, zorder=zorder+1, **kwargs)
    return Pos(x - 0.5*w, y), Pos(x + 0.5*w, y)

def resistance_v(ax, pos, label='', align='right', lw=None, color=None, facecolor=None, alpha=None, zorder=None, **kwargs)

Draw a vertical resistance.

Parameters

ax : matplotlib axes

Axes where to draw the resistance.

pos : Pos or 2-tuple of floats

x and y-coordinate of position of the center of the resistance.

label : string

Optional label for the resistance.

align : 'left', 'right', 'center'

Position the label to th left, right or in the center of the resistance.

lw : float, int

Linewidth for drawing the outline of the resistance. Defaults to circuits.linewidth rcParams settings.

color matplotlib color

Color for the outline of the resistance.

Defaults to circuits.color rcParams settings.

facecolor matplotlib color

Color for filling the resistance.

Defaults to circuits.facecolor rcParams settings.

alpha : float

Alpha value for the face color. Defaults to circuits.alpha rcParams settings.

zorder : int

zorder for the resistance and the label. Defaults to circuits.zorder rcParams settings.

kwargs : key-word arguments

Passed on to ax.text() used to print the label. Defaults to circuits.font rcParams settings.

Returns

posb : Pos

Coordinates of the bottom end of the resistance.

post : Pos

Coordinates of the top end of the resistance.

Raises

Valueerror

Invalid value for align.

Expand source code

def resistance_v(ax, pos, label='', align='right', lw=None, color=None,
                 facecolor=None, alpha=None, zorder=None, **kwargs):
    """ Draw a vertical resistance.

    Parameters
    ----------
    ax: matplotlib axes
        Axes where to draw the resistance.
    pos: Pos or 2-tuple of floats
        x and y-coordinate of position of the center of the resistance.
    label: string
        Optional label for the resistance.
    align: 'left', 'right', 'center'
        Position the label to th left, right or in the center of the resistance.
    lw: float, int
        Linewidth for drawing the outline of the resistance.
        Defaults to `circuits.linewidth` rcParams settings.
    color matplotlib color
        Color for the outline of the resistance.
        Defaults to `circuits.color` rcParams settings.
    facecolor matplotlib color
        Color for filling the resistance.
        Defaults to `circuits.facecolor` rcParams settings.
    alpha: float
        Alpha value for the face color.
        Defaults to `circuits.alpha` rcParams settings.
    zorder: int
        zorder for the resistance and the label.
        Defaults to `circuits.zorder` rcParams settings.
    kwargs: key-word arguments
        Passed on to `ax.text()` used to print the label.
        Defaults to `circuits.font` rcParams settings.

    Returns
    -------
    posb: Pos
        Coordinates of the bottom end of the resistance.
    post: Pos
        Coordinates of the top end of the resistance.

    Raises
    ------
    ValueError:
        Invalid value for `align`.
    """
    if lw is None:
        lw = mpl.rcParams['circuits.linewidth']
    if color is None:
        color = mpl.rcParams['circuits.color']
    if facecolor is None:
        facecolor = mpl.rcParams['circuits.facecolor']
    if alpha is None:
        alpha = mpl.rcParams['circuits.alpha']
    if zorder is None:
        zorder = mpl.rcParams['circuits.zorder']
    for k in mpl.rcParams['circuits.font']:
        if not k in kwargs:
            kwargs[k] = mpl.rcParams['circuits.font'][k]
    w = 0.5*mpl.rcParams['circuits.scale']
    h = mpl.rcParams['circuits.scale']
    x, y = pos
    ax.add_patch(Rectangle((x - 0.5*w, y - 0.5*h), w, h,
                           zorder=zorder, edgecolor='none',
                           facecolor=facecolor, alpha=alpha))
    ax.add_patch(Rectangle((x - 0.5*w, y - 0.5*h), w, h,
                           zorder=zorder+1, edgecolor=color,
                           facecolor='none', lw=lw))
    if label:
        ha = 'center'
        va = 'center'
        if align == 'right':
            xx = 0.7*w
            ha = 'left'
        elif align == 'left':
            xx = -0.7*w
            ha = 'right'
        elif align == 'center':
            xx = 0
        else:
            raise ValueError('align must be one of "left", "right", or "center"')
        if not 'ha' in kwargs and not 'horizontalalignment' in kwargs:
            kwargs['ha'] = ha
        if not 'va' in kwargs and not 'verticalalignment' in kwargs:
            kwargs['va'] = va
        ax.text(x + xx, y, label, zorder=zorder+1, **kwargs)
    return Pos(x, y - 0.5*h), Pos(x, y + 0.5*h)

def resistance(ax, pos, angle=0, label='', align='above', lw=None, color=None, facecolor=None, alpha=None, zorder=None, **kwargs)

Draw an arbitrarily rotated resistance.

Parameters

ax : matplotlib axes

Axes where to draw the resistance bar.

pos : Pos or 2-tuple of floats

x and y-coordinate of position of the center of the resistance.

angle : float

Rotation angle in degrees.

label : string

Optional label for the resistance.

align : 'above', 'below', 'center'

Position the label above, below or in the center of the non-rotated resistance.

lw : float, int

Linewidth for drawing the outline of the resistance. Defaults to circuits.linewidth rcParams settings.

color matplotlib color

Color for the outline of the resistance.

Defaults to circuits.color rcParams settings.

facecolor matplotlib color

Color for filling the resistance.

Defaults to circuits.facecolor rcParams settings.

alpha : float

Alpha value for the face color. Defaults to circuits.alpha rcParams settings.

zorder : int

zorder for the resistance and the label. Defaults to circuits.zorder rcParams settings.

kwargs : key-word arguments

Passed on to ax.text() used to print the label. Defaults to circuits.font rcParams settings.

Returns

posl : Pos

Coordinates of the left end of the resistance.

posr : Pos

Coordinates of the right end of the resistance.

Raises

Valueerror

Invalid value for align.

Expand source code

def resistance(ax, pos, angle=0, label='', align='above', lw=None,
               color=None, facecolor=None, alpha=None, zorder=None,
               **kwargs):
    """Draw an arbitrarily rotated resistance.

    Parameters
    ----------
    ax: matplotlib axes
        Axes where to draw the resistance bar.
    pos: Pos or 2-tuple of floats
        x and y-coordinate of position of the center of the resistance.
    angle: float
        Rotation angle in degrees.
    label: string
        Optional label for the resistance.
    align: 'above', 'below', 'center'
        Position the label above, below or in the center of the
        non-rotated resistance.
    lw: float, int
        Linewidth for drawing the outline of the resistance.
        Defaults to `circuits.linewidth` rcParams settings.
    color matplotlib color
        Color for the outline of the resistance.
        Defaults to `circuits.color` rcParams settings.
    facecolor matplotlib color
        Color for filling the resistance.
        Defaults to `circuits.facecolor` rcParams settings.
    alpha: float
        Alpha value for the face color.
        Defaults to `circuits.alpha` rcParams settings.
    zorder: int
        zorder for the resistance and the label.
        Defaults to `circuits.zorder` rcParams settings.
    kwargs: key-word arguments
        Passed on to `ax.text()` used to print the label.
        Defaults to `circuits.font` rcParams settings.

    Returns
    -------
    posl: Pos
        Coordinates of the left end of the resistance.
    posr: Pos
        Coordinates of the right end of the resistance.

    Raises
    ------
    ValueError:
        Invalid value for `align`.
    """
    if lw is None:
        lw = mpl.rcParams['circuits.linewidth']
    if color is None:
        color = mpl.rcParams['circuits.color']
    if facecolor is None:
        facecolor = mpl.rcParams['circuits.facecolor']
    if alpha is None:
        alpha = mpl.rcParams['circuits.alpha']
    if zorder is None:
        zorder = mpl.rcParams['circuits.zorder']
    for k in mpl.rcParams['circuits.font']:
        if not k in kwargs:
            kwargs[k] = mpl.rcParams['circuits.font'][k]
    w = mpl.rcParams['circuits.scale']
    h = 0.5*mpl.rcParams['circuits.scale']
    x, y = pos
    transform = mpt.Affine2D().rotate(np.radians(angle)).translate(*pos)
    ax.add_patch(Rectangle((-0.5*w, -0.5*h), w, h,
                           transform=transform + ax.transData,
                           zorder=zorder, edgecolor='none',
                           facecolor=facecolor, alpha=alpha))
    ax.add_patch(Rectangle((-0.5*w, -0.5*h), w, h,
                           transform=transform + ax.transData,
                           zorder=zorder+1, edgecolor=color,
                           facecolor='none', lw=lw))
    if label:
        if angle < 0:
            angle += 360
        ha = 'center'
        va = 'center'
        if align == 'above':
            pos = np.array(((0, 0.8*h),))
            if angle > 45 and angle < 45 + 90:
                ha = 'right'
            elif angle > 45 + 180 and angle < 45 + 270:
                ha = 'left'
            if angle > 45 + 270 and angle < 45:
                va = 'bottom'
            elif angle > 45 + 90 and angle < 45 + 180:
                va = 'top'
        elif align == 'below':
            pos = np.array(((0, -0.8*h),))
            if angle > 45 and angle < 45 + 90:
                ha = 'left'
            elif angle > 45 + 180 and angle < 45 + 270:
                ha = 'right'
            if angle > 45 + 270 and angle < 45:
                va = 'top'
            elif angle > 45 + 90 and angle < 45 + 180:
                va = 'bottom'
        elif align == 'center':
            pos = np.array(((0, 0),))
        else:
            raise ValueError('align must be one of "above", "bottom", or "center"')
        pos = transform.transform(pos)
        if not 'ha' in kwargs and not 'horizontalalignment' in kwargs:
            kwargs['ha'] = ha
        if not 'va' in kwargs and not 'verticalalignment' in kwargs:
            kwargs['va'] = va
        ax.text(pos[0,0], pos[0,1], label, zorder=zorder+1, **kwargs)
    nodes = np.array(((-0.5*w, 0), (+0.5*w, 0)))
    nodes = transform.transform(nodes)
    return Pos(*nodes[0,:]),  Pos(*nodes[1,:])

def capacitance_h(ax, pos, label='', align='above', lw=None, color=None, zorder=None, **kwargs)

Draw a horizontal capacitance.

Parameters

ax : matplotlib axes

Axes where to draw the capacitance.

pos : Pos or 2-tuple of floats

x and y-coordinate of position of the center of the capacitance.

label : string

Optional label for the capacitance.

align : 'above', 'below'

Position the label above or below the capacitance.

lw : float, int

Linewidth for drawing the outline of the capacitance. Defaults to circuits.linewidth rcParams settings.

color matplotlib color

Color for the outline of the capacitance.

Defaults to circuits.color rcParams settings.

zorder : int

zorder for the capacitance and the label. Defaults to circuits.zorder rcParams settings.

kwargs : key-word arguments

Passed on to ax.text() used to print the label. Defaults to circuits.font rcParams settings.

Returns

posl : Pos

Coordinates of the left end of the capacitance.

posr : Pos

Coordinates of the right end of the capacitance.

Raises

Valueerror

Invalid value for align.

Expand source code

def capacitance_h(ax, pos, label='', align='above', lw=None,
                  color=None, zorder=None, **kwargs):
    """ Draw a horizontal capacitance.

    Parameters
    ----------
    ax: matplotlib axes
        Axes where to draw the capacitance.
    pos: Pos or 2-tuple of floats
        x and y-coordinate of position of the center of the capacitance.
    label: string
        Optional label for the capacitance.
    align: 'above', 'below'
        Position the label above or below the capacitance.
    lw: float, int
        Linewidth for drawing the outline of the capacitance.
        Defaults to `circuits.linewidth` rcParams settings.
    color matplotlib color
        Color for the outline of the capacitance.
        Defaults to `circuits.color` rcParams settings.
    zorder: int
        zorder for the capacitance and the label.
        Defaults to `circuits.zorder` rcParams settings.
    kwargs: key-word arguments
        Passed on to `ax.text()` used to print the label.
        Defaults to `circuits.font` rcParams settings.

    Returns
    -------
    posl: Pos
        Coordinates of the left end of the capacitance.
    posr: Pos
        Coordinates of the right end of the capacitance.

    Raises
    ------
    ValueError:
        Invalid value for `align`.
    """
    if lw is None:
        lw = mpl.rcParams['circuits.linewidth']
    if color is None:
        color = mpl.rcParams['circuits.color']
    if zorder is None:
        zorder = mpl.rcParams['circuits.zorder']
    for k in mpl.rcParams['circuits.font']:
        if not k in kwargs:
            kwargs[k] = mpl.rcParams['circuits.font'][k]
    w = mpl.rcParams['circuits.scale']
    h = mpl.rcParams['circuits.scale']*0.8/3
    x, y = pos
    ax.plot([x - 0.5*h, x - 0.5*h], [y - 0.5*w, y + 0.5*w],
            zorder=zorder, lw=lw, color=color)
    ax.plot([x + 0.5*h, x + 0.5*h], [y - 0.5*w, y + 0.5*w],
            zorder=zorder, lw=lw, color=color)
    if label:
        yy = 0
        ha = 'center'
        va = 'center'
        if align == 'above':
            yy = 0.6*w
            va = 'bottom'
        elif align == 'below':
            yy = -0.6*w
            va = 'top'
        else:
            raise ValueError('align must be one of "above" or "bottom"')
        if not 'ha' in kwargs and not 'horizontalalignment' in kwargs:
            kwargs['ha'] = ha
        if not 'va' in kwargs and not 'verticalalignment' in kwargs:
            kwargs['va'] = va
        ax.text(x, y + yy, label, zorder=zorder, **kwargs)
    return Pos(x - 0.5*h, y), Pos(x + 0.5*h, y)

def capacitance_v(ax, pos, label='', align='right', lw=None, color=None, zorder=None, **kwargs)

Draw a vertical capacitance.

Parameters

ax : matplotlib axes

Axes where to draw the capacitance.

pos : Pos or 2-tuple of floats

x and y-coordinate of position of the center of the capacitance.

label : string

Optional label for the capacitance.

align : 'left', 'right'

Position the label to the left or to the right of the capacitance.

lw : float, int

Linewidth for drawing the outline of the capacitance. Defaults to circuits.linewidth rcParams settings.

color matplotlib color

Color for the outline of the capacitance.

Defaults to circuits.color rcParams settings.

zorder : int

zorder for the capacitance and the label. Defaults to circuits.zorder rcParams settings.

kwargs : key-word arguments

Passed on to ax.text() used to print the label. Defaults to circuits.font rcParams settings.

Returns

posb : Pos

Coordinates of the bottom end of the capacitance.

post : Pos

Coordinates of the top end of the capacitance.

Raises

Valueerror

Invalid value for align.

Expand source code

def capacitance_v(ax, pos, label='', align='right', lw=None,
                  color=None, zorder=None, **kwargs):
    """ Draw a vertical capacitance.

    Parameters
    ----------
    ax: matplotlib axes
        Axes where to draw the capacitance.
    pos: Pos or 2-tuple of floats
        x and y-coordinate of position of the center of the capacitance.
    label: string
        Optional label for the capacitance.
    align: 'left', 'right'
        Position the label to the left or to the right of the capacitance.
    lw: float, int
        Linewidth for drawing the outline of the capacitance.
        Defaults to `circuits.linewidth` rcParams settings.
    color matplotlib color
        Color for the outline of the capacitance.
        Defaults to `circuits.color` rcParams settings.
    zorder: int
        zorder for the capacitance and the label.
        Defaults to `circuits.zorder` rcParams settings.
    kwargs: key-word arguments
        Passed on to `ax.text()` used to print the label.
        Defaults to `circuits.font` rcParams settings.

    Returns
    -------
    posb: Pos
        Coordinates of the bottom end of the capacitance.
    post: Pos
        Coordinates of the top end of the capacitance.

    Raises
    ------
    ValueError:
        Invalid value for `align`.
    """
    if lw is None:
        lw = mpl.rcParams['circuits.linewidth']
    if color is None:
        color = mpl.rcParams['circuits.color']
    if zorder is None:
        zorder = mpl.rcParams['circuits.zorder']
    for k in mpl.rcParams['circuits.font']:
        if not k in kwargs:
            kwargs[k] = mpl.rcParams['circuits.font'][k]
    w = mpl.rcParams['circuits.scale']
    h = mpl.rcParams['circuits.scale']*0.8/3
    x, y = pos
    ax.plot([x - 0.5*w, x + 0.5*w], [y + 0.5*h, y + 0.5*h],
            zorder=zorder, lw=lw, color=color)
    ax.plot([x - 0.5*w, x + 0.5*w], [y - 0.5*h, y - 0.5*h],
            zorder=zorder, lw=lw, color=color)
    if label:
        ha = 'center'
        va = 'center'
        if align == 'right':
            xx = 0.6*w
            ha = 'left'
        elif align == 'left':
            xx = -0.6*w
            ha = 'right'
        else:
            raise ValueError('align must be one of "left" or "right"')
        if not 'ha' in kwargs and not 'horizontalalignment' in kwargs:
            kwargs['ha'] = ha
        if not 'va' in kwargs and not 'verticalalignment' in kwargs:
            kwargs['va'] = va
        ax.text(x + xx, y, label, zorder=zorder, **kwargs)
    return Pos(x, y - 0.5*h), Pos(x, y + 0.5*h)

def battery_h(ax, pos, label='', align='above', lw=None, color=None, zorder=None, **kwargs)

Draw a horizontal battery (voltage source).

Parameters

ax : matplotlib axes

Axes where to draw the battery.

pos : Pos or 2-tuple of floats

x and y-coordinate of position of the center of the battery.

label : string

Optional label for the battery.

align : 'above', 'below'

Position the label above or below the battery.

lw : float, int

Linewidth for drawing the outline of the battery. Defaults to circuits.linewidth rcParams settings.

color matplotlib color

Color for the outline of the battery.

Defaults to circuits.color rcParams settings.

zorder : int

zorder for the battery and the label. Defaults to circuits.zorder rcParams settings.

kwargs : key-word arguments

Passed on to ax.text() used to print the label. Defaults to circuits.font rcParams settings.

Returns

posl : Pos

Coordinates of the left end of the battery.

posr : Pos

Coordinates of the right end of the battery.

Raises

Valueerror

Invalid value for align.

Expand source code

def battery_h(ax, pos, label='', align='above', lw=None, color=None,
              zorder=None, **kwargs):
    """ Draw a horizontal battery (voltage source).

    Parameters
    ----------
    ax: matplotlib axes
        Axes where to draw the battery.
    pos: Pos or 2-tuple of floats
        x and y-coordinate of position of the center of the battery.
    label: string
        Optional label for the battery.
    align: 'above', 'below'
        Position the label above or below the battery.
    lw: float, int
        Linewidth for drawing the outline of the battery.
        Defaults to `circuits.linewidth` rcParams settings.
    color matplotlib color
        Color for the outline of the battery.
        Defaults to `circuits.color` rcParams settings.
    zorder: int
        zorder for the battery and the label.
        Defaults to `circuits.zorder` rcParams settings.
    kwargs: key-word arguments
        Passed on to `ax.text()` used to print the label.
        Defaults to `circuits.font` rcParams settings.

    Returns
    -------
    posl: Pos
        Coordinates of the left end of the battery.
    posr: Pos
        Coordinates of the right end of the battery.

    Raises
    ------
    ValueError:
        Invalid value for `align`.
    """
    if lw is None:
        lw = mpl.rcParams['circuits.linewidth']
    if color is None:
        color = mpl.rcParams['circuits.color']
    if zorder is None:
        zorder = mpl.rcParams['circuits.zorder']
    for k in mpl.rcParams['circuits.font']:
        if not k in kwargs:
            kwargs[k] = mpl.rcParams['circuits.font'][k]
    w = mpl.rcParams['circuits.scale']*4/3
    h = mpl.rcParams['circuits.scale']*0.8/3
    x, y = pos
    ax.plot([x - 0.5*h, x - 0.5*h], [y - 0.5*w, y + 0.5*w],
            zorder=zorder, lw=lw, color=color)
    ax.plot([x + 0.5*h, x + 0.5*h], [y - 0.25*w, y + 0.25*w],
            zorder=zorder, lw=lw, color=color)
    if label:
        yy = 0
        ha = 'center'
        va = 'center'
        if align == 'above':
            yy = 0.6*w
            va = 'bottom'
        elif align == 'below':
            yy = -0.6*w
            va = 'top'
        else:
            raise ValueError('align must be one of "above" or "bottom"')
        if not 'ha' in kwargs and not 'horizontalalignment' in kwargs:
            kwargs['ha'] = ha
        if not 'va' in kwargs and not 'verticalalignment' in kwargs:
            kwargs['va'] = va
        ax.text(x, y + yy, label, zorder=zorder, **kwargs)
    return Pos(x - 0.5*h, y), Pos(x + 0.5*h, y)

def battery_v(ax, pos, label='', align='right', lw=None, color=None, zorder=None, **kwargs)

Draw a vertical battery (voltage source).

Parameters

ax : matplotlib axes

Axes where to draw the battery.

pos : Pos or 2-tuple of floats

x and y-coordinate of position of the center of the battery.

label : string

Optional label for the battery.

align : 'left', 'right'

Position the label to the left or to the right of the battery.

lw : float, int

Linewidth for drawing the outline of the battery. Defaults to circuits.linewidth rcParams settings.

color matplotlib color

Color for the outline of the battery.

Defaults to circuits.color rcParams settings.

zorder : int

zorder for the battery and the label. Defaults to circuits.zorder rcParams settings.

kwargs : key-word arguments

Passed on to ax.text() used to print the label. Defaults to circuits.font rcParams settings.

Returns

posb : Pos

Coordinates of the bottom end of the battery.

post : Pos

Coordinates of the top end of the battery.

Raises

Valueerror

Invalid value for align.

Expand source code

def battery_v(ax, pos, label='', align='right', lw=None, color=None,
              zorder=None, **kwargs):
    """ Draw a vertical battery (voltage source).

    Parameters
    ----------
    ax: matplotlib axes
        Axes where to draw the battery.
    pos: Pos or 2-tuple of floats
        x and y-coordinate of position of the center of the battery.
    label: string
        Optional label for the battery.
    align: 'left', 'right'
        Position the label to the left or to the right of the battery.
    lw: float, int
        Linewidth for drawing the outline of the battery.
        Defaults to `circuits.linewidth` rcParams settings.
    color matplotlib color
        Color for the outline of the battery.
        Defaults to `circuits.color` rcParams settings.
    zorder: int
        zorder for the battery and the label.
        Defaults to `circuits.zorder` rcParams settings.
    kwargs: key-word arguments
        Passed on to `ax.text()` used to print the label.
        Defaults to `circuits.font` rcParams settings.

    Returns
    -------
    posb: Pos
        Coordinates of the bottom end of the battery.
    post: Pos
        Coordinates of the top end of the battery.

    Raises
    ------
    ValueError:
        Invalid value for `align`.
    """
    if lw is None:
        lw = mpl.rcParams['circuits.linewidth']
    if color is None:
        color = mpl.rcParams['circuits.color']
    if zorder is None:
        zorder = mpl.rcParams['circuits.zorder']
    for k in mpl.rcParams['circuits.font']:
        if not k in kwargs:
            kwargs[k] = mpl.rcParams['circuits.font'][k]
    w = mpl.rcParams['circuits.scale']*4/3
    h = mpl.rcParams['circuits.scale']*0.8/3
    x, y = pos
    ax.plot([x - 0.5*w, x + 0.5*w], [y + 0.5*h, y + 0.5*h],
            zorder=zorder, lw=lw, color=color)
    ax.plot([x - 0.25*w, x + 0.25*w], [y - 0.5*h, y - 0.5*h],
            zorder=zorder, lw=lw, color=color)
    if label:
        ha = 'center'
        va = 'center'
        if align == 'right':
            xx = 0.6*w
            ha = 'left'
        elif align == 'left':
            xx = -0.6*w
            ha = 'right'
        else:
            raise ValueError('align must be one of "left" or "right"')
        if not 'ha' in kwargs and not 'horizontalalignment' in kwargs:
            kwargs['ha'] = ha
        if not 'va' in kwargs and not 'verticalalignment' in kwargs:
            kwargs['va'] = va
        ax.text(x + xx, y, label, zorder=zorder, **kwargs)
    return Pos(x, y - 0.5*h), Pos(x, y + 0.5*h)

def ground(ax, pos, label='', align='right', lw=None, color=None, zorder=None, **kwargs)

Draw ground.

Parameters

ax : matplotlib axes

Axes where to draw the battery.

pos : Pos or 2-tuple of floats

x and y-coordinate of position of the center of the battery.

label : string

Optional label for the battery.

align : 'left', 'right'

Position the label to the left or to the right of the ground.

lw : float, int

Linewidth for drawing the outline of the battery. Defaults to circuits.linewidth rcParams settings.

color matplotlib color

Color for the outline of the battery.

Defaults to circuits.color rcParams settings.

zorder : int

zorder for the battery and the label. Defaults to circuits.zorder rcParams settings.

kwargs : key-word arguments

Passed on to ax.text() used to print the label. Defaults to circuits.font rcParams settings.

Returns

pos : Pos

Coordinates of the top end of ground.

Raises

Valueerror

Invalid value for align.

Expand source code

def ground(ax, pos, label='', align='right', lw=None, color=None,
           zorder=None, **kwargs):
    """ Draw ground.

    Parameters
    ----------
    ax: matplotlib axes
        Axes where to draw the battery.
    pos: Pos or 2-tuple of floats
        x and y-coordinate of position of the center of the battery.
    label: string
        Optional label for the battery.
    align: 'left', 'right'
        Position the label to the left or to the right of the ground.
    lw: float, int
        Linewidth for drawing the outline of the battery.
        Defaults to `circuits.linewidth` rcParams settings.
    color matplotlib color
        Color for the outline of the battery.
        Defaults to `circuits.color` rcParams settings.
    zorder: int
        zorder for the battery and the label.
        Defaults to `circuits.zorder` rcParams settings.
    kwargs: key-word arguments
        Passed on to `ax.text()` used to print the label.
        Defaults to `circuits.font` rcParams settings.

    Returns
    -------
    pos: Pos
        Coordinates of the top end of ground.

    Raises
    ------
    ValueError:
        Invalid value for `align`.
    """
    if lw is None:
        lw = mpl.rcParams['circuits.linewidth']
    if color is None:
        color = mpl.rcParams['circuits.color']
    if zorder is None:
        zorder = mpl.rcParams['circuits.zorder']
    for k in mpl.rcParams['circuits.font']:
        if not k in kwargs:
            kwargs[k] = mpl.rcParams['circuits.font'][k]
    w = mpl.rcParams['circuits.scale']*0.8
    h = mpl.rcParams['circuits.scale']*0.17
    x, y = pos
    ax.plot([x - 0.5*w, x + 0.5*w], [y + h, y + h],
            zorder=zorder, lw=lw, color=color)
    ax.plot([x - 0.3*w, x + 0.3*w], [y, y],
            zorder=zorder, lw=lw, color=color)
    ax.plot([x - 0.06*w, x + 0.06*w], [y - h, y - h],
            zorder=zorder, lw=lw, color=color)
    if label:
        ha = 'center'
        va = 'center'
        if align == 'right':
            xx = 0.7*w
            ha = 'left'
        elif align == 'left':
            xx = -0.7*w
            ha = 'right'
        else:
            raise ValueError('align must be one of "left" or "right"')
        if not 'ha' in kwargs and not 'horizontalalignment' in kwargs:
            kwargs['ha'] = ha
        if not 'va' in kwargs and not 'verticalalignment' in kwargs:
            kwargs['va'] = va
        ax.text(x + xx, y, label, zorder=zorder, **kwargs)
    return Pos(x, y + h)

def opamp_l(ax, pos, label='', align='above', lw=None, color=None, facecolor=None, alpha=None, zorder=None, **kwargs)

Draw an operational amplifier with inputs on the left.

Parameters

ax : matplotlib axes

Axes where to draw the opamp.

pos : Pos or 2-tuple of floats

x and y-coordinate of position of the center of the opamp.

label : string

Optional label for the opamp.

align : 'above', 'below', 'center'

Position the label above, below or in the center of the opamp.

lw : float, int

Linewidth for drawing the outline of the opamp. Defaults to circuits.linewidth rcParams settings.

color matplotlib color

Color for the outline of the opamp.

Defaults to circuits.color rcParams settings.

facecolor matplotlib color

Color for filling the opamp.

Defaults to circuits.facecolor rcParams settings.

alpha : float

Alpha value for the face color. Defaults to circuits.alpha rcParams settings.

zorder : int

zorder for the opamp and the label. Defaults to circuits.zorder rcParams settings.

kwargs : key-word arguments

Passed on to ax.text() used to print the label. Defaults to circuits.font rcParams settings.

Returns

pospos : Pos

Coordinates of the positive (upper) input of the opamp.

posneg : Pos

Coordinates of the negative (lower) input of the opamp.

posout : Pos

Coordinates of the output of the opamp.

posgnd : Pos

Coordinates of the ground supply of the opamp.

Raises

Valueerror

Invalid value for align.

Expand source code

def opamp_l(ax, pos, label='', align='above', lw=None, color=None,
            facecolor=None, alpha=None, zorder=None, **kwargs):
    """ Draw an operational amplifier with inputs on the left.

    Parameters
    ----------
    ax: matplotlib axes
        Axes where to draw the opamp.
    pos: Pos or 2-tuple of floats
        x and y-coordinate of position of the center of the opamp.
    label: string
        Optional label for the opamp.
    align: 'above', 'below', 'center'
        Position the label above, below or in the center of the opamp.
    lw: float, int
        Linewidth for drawing the outline of the opamp.
        Defaults to `circuits.linewidth` rcParams settings.
    color matplotlib color
        Color for the outline of the opamp.
        Defaults to `circuits.color` rcParams settings.
    facecolor matplotlib color
        Color for filling the opamp.
        Defaults to `circuits.facecolor` rcParams settings.
    alpha: float
        Alpha value for the face color.
        Defaults to `circuits.alpha` rcParams settings.
    zorder: int
        zorder for the opamp and the label.
        Defaults to `circuits.zorder` rcParams settings.
    kwargs: key-word arguments
        Passed on to `ax.text()` used to print the label.
        Defaults to `circuits.font` rcParams settings.

    Returns
    -------
    pospos: Pos
        Coordinates of the positive (upper) input of the opamp.
    posneg: Pos
        Coordinates of the negative (lower) input of the opamp.
    posout: Pos
        Coordinates of the output of the opamp.
    posgnd: Pos
        Coordinates of the ground supply of the opamp.

    Raises
    ------
    ValueError:
        Invalid value for `align`.
    """
    if lw is None:
        lw = mpl.rcParams['circuits.linewidth']
    if color is None:
        color = mpl.rcParams['circuits.color']
    if facecolor is None:
        facecolor = mpl.rcParams['circuits.facecolor']
    if alpha is None:
        alpha = mpl.rcParams['circuits.alpha']
    if zorder is None:
        zorder = mpl.rcParams['circuits.zorder']
    for k in mpl.rcParams['circuits.font']:
        if not k in kwargs:
            kwargs[k] = mpl.rcParams['circuits.font'][k]
    a = mpl.rcParams['circuits.scale']*5/3
    r = a/2/np.sqrt(3)
    x, y = pos
    xy = np.array([[x - r, y - 0.5*a], [x - r, y + 0.5*a], [x + 2*r, y]])
    ax.add_patch(Polygon(xy, closed=True,
                         zorder=zorder, edgecolor='none',
                         facecolor=facecolor, alpha=alpha))
    ax.add_patch(Polygon(xy, closed=True,
                         zorder=zorder+1, edgecolor=color,
                         facecolor='none', lw=lw))
    ax.text(x - 0.8*r, y + 0.21*a, '$+$', ha='left', va='center',
            fontsize='x-small', color=color, zorder=zorder+1)
    ax.text(x - 0.8*r, y - 0.19*a, '$-$', ha='left', va='center',
            fontsize='x-small', color=color, zorder=zorder+1)
    if label:
        ha = 'left'
        va = 'center'
        if align == 'above':
            yy = 1.4*r
            va = 'bottom'
        elif align == 'below':
            yy = -1.4*r
            va = 'top'
        elif align == 'center':
            yy = 0
        else:
            raise ValueError('align must be one of "above", "bottom", or "center"')
        if not 'ha' in kwargs and not 'horizontalalignment' in kwargs:
            kwargs['ha'] = ha
        if not 'va' in kwargs and not 'verticalalignment' in kwargs:
            kwargs['va'] = va
        ax.text(x, y + yy, label, zorder=zorder+1, **kwargs)
    return Pos(x - r, y - 0.2*a), Pos(x - r, y + 0.2*a), Pos(x + 2*r, y), Pos(x, y-1.2*r)

def opamp_r(ax, pos, label='', align='above', lw=None, color=None, facecolor=None, alpha=None, zorder=None, **kwargs)

Draw an operational amplifier with inputs on the right.

Parameters

ax : matplotlib axes

Axes where to draw the opamp.

pos : Pos or 2-tuple of floats

x and y-coordinate of position of the center of the opamp.

label : string

Optional label for the opamp.

align : 'above', 'below', 'center'

Position the label above, below or in the center of the opamp.

lw : float, int

Linewidth for drawing the outline of the opamp. Defaults to circuits.linewidth rcParams settings.

color matplotlib color

Color for the outline of the opamp.

Defaults to circuits.color rcParams settings.

facecolor matplotlib color

Color for filling the opamp.

Defaults to circuits.facecolor rcParams settings.

alpha : float

Alpha value for the face color. Defaults to circuits.alpha rcParams settings.

zorder : int

zorder for the opamp and the label. Defaults to circuits.zorder rcParams settings.

kwargs : key-word arguments

Passed on to ax.text() used to print the label. Defaults to circuits.font rcParams settings.

Returns

pospos : Pos

Coordinates of the positive (upper) input of the opamp.

posneg : Pos

Coordinates of the negative (lower) input of the opamp.

posout : Pos

Coordinates of the output of the opamp.

posgnd : Pos

Coordinates of the ground supply of the opamp.

Raises

Valueerror

Invalid value for align.

Expand source code

def opamp_r(ax, pos, label='', align='above', lw=None, color=None,
            facecolor=None, alpha=None, zorder=None, **kwargs):
    """ Draw an operational amplifier with inputs on the right.

    Parameters
    ----------
    ax: matplotlib axes
        Axes where to draw the opamp.
    pos: Pos or 2-tuple of floats
        x and y-coordinate of position of the center of the opamp.
    label: string
        Optional label for the opamp.
    align: 'above', 'below', 'center'
        Position the label above, below or in the center of the opamp.
    lw: float, int
        Linewidth for drawing the outline of the opamp.
        Defaults to `circuits.linewidth` rcParams settings.
    color matplotlib color
        Color for the outline of the opamp.
        Defaults to `circuits.color` rcParams settings.
    facecolor matplotlib color
        Color for filling the opamp.
        Defaults to `circuits.facecolor` rcParams settings.
    alpha: float
        Alpha value for the face color.
        Defaults to `circuits.alpha` rcParams settings.
    zorder: int
        zorder for the opamp and the label.
        Defaults to `circuits.zorder` rcParams settings.
    kwargs: key-word arguments
        Passed on to `ax.text()` used to print the label.
        Defaults to `circuits.font` rcParams settings.

    Returns
    -------
    pospos: Pos
        Coordinates of the positive (upper) input of the opamp.
    posneg: Pos
        Coordinates of the negative (lower) input of the opamp.
    posout: Pos
        Coordinates of the output of the opamp.
    posgnd: Pos
        Coordinates of the ground supply of the opamp.

    Raises
    ------
    ValueError:
        Invalid value for `align`.
    """
    if lw is None:
        lw = mpl.rcParams['circuits.linewidth']
    if color is None:
        color = mpl.rcParams['circuits.color']
    if facecolor is None:
        facecolor = mpl.rcParams['circuits.facecolor']
    if alpha is None:
        alpha = mpl.rcParams['circuits.alpha']
    if zorder is None:
        zorder = mpl.rcParams['circuits.zorder']
    for k in mpl.rcParams['circuits.font']:
        if not k in kwargs:
            kwargs[k] = mpl.rcParams['circuits.font'][k]
    a = mpl.rcParams['circuits.scale']*5/3
    r = a/2/np.sqrt(3)
    x, y = pos
    xy = np.array([[x + r, y - 0.5*a], [x + r, y + 0.5*a], [x - 2*r, y]])
    ax.add_patch(Polygon(xy, closed=True,
                         zorder=zorder, edgecolor='none',
                         facecolor=facecolor, alpha=alpha))
    ax.add_patch(Polygon(xy, closed=True,
                         zorder=zorder+1, edgecolor=color,
                         facecolor='none', lw=lw))
    ax.text(x + 0.8*r, y + 0.21*a, '$+$', ha='right', va='center',
            fontsize='x-small', color=color, zorder=zorder+1)
    ax.text(x + 0.8*r, y - 0.19*a, '$-$', ha='right', va='center',
            fontsize='x-small', color=color, zorder=zorder+1)
    if label:
        ha = 'right'
        va = 'center'
        if align == 'above':
            yy = 1.4*r
            va = 'bottom'
        elif align == 'below':
            yy = -1.4*r
            va = 'top'
        elif align == 'center':
            yy = 0
        else:
            raise ValueError('align must be one of "above", "bottom", or "center"')
        if not 'ha' in kwargs and not 'horizontalalignment' in kwargs:
            kwargs['ha'] = ha
        if not 'va' in kwargs and not 'verticalalignment' in kwargs:
            kwargs['va'] = va
        ax.text(x, y + yy, label, zorder=zorder+1, **kwargs)
    return Pos(x + r, y - 0.2*a), Pos(x + r, y + 0.2*a), Pos(x - 2*r, y), Pos(x, y-1.2*r)

def node(ax, pos, label='', align='northeast', color=None, zorder=None, **kwargs)

Draw a node connecting lines.

Parameters

ax : matplotlib axes

Axes where to draw the node.

pos : Pos or 2-tuple of floats

x and y-coordinate of position of the center of the node.

label : string

Optional label for the node.

align : 'left', 'right', 'above', 'below', 'north', 'south', 'west', 'east', 'northwest', 'northeast', 'southwest', 'southeast'

Position of the label relative to the node.

color matplotlib color

Color of the node.

Defaults to circuits.color rcParams settings.

zorder : int

zorder for the node. Defaults to circuits.zorder rcParams settings.

kwargs : key-word arguments

Passed on to ax.text() used to print the label. Defaults to circuits.font rcParams settings.

Returns

pos : Pos

Coordinates of the node.

Expand source code

def node(ax, pos, label='', align='northeast', color=None,
         zorder=None, **kwargs):
    """ Draw a node connecting lines.

    Parameters
    ----------
    ax: matplotlib axes
        Axes where to draw the node.
    pos: Pos or 2-tuple of floats
        x and y-coordinate of position of the center of the node.
    label: string
        Optional label for the node.
    align: 'left', 'right', 'above', 'below', 'north', 'south', 'west', 'east', 'northwest', 'northeast', 'southwest', 'southeast'
        Position of the label relative to the node.
    color matplotlib color
        Color of the node.
        Defaults to `circuits.color` rcParams settings.
    zorder: int
        zorder for the node.
        Defaults to `circuits.zorder` rcParams settings.
    kwargs: key-word arguments
        Passed on to `ax.text()` used to print the label.
        Defaults to `circuits.font` rcParams settings.

    Returns
    -------
    pos: Pos
        Coordinates of the node.
    """
    if color is None:
        color = mpl.rcParams['circuits.color']
    if zorder is None:
        zorder = mpl.rcParams['circuits.zorder']
    for k in mpl.rcParams['circuits.font']:
        if not k in kwargs:
            kwargs[k] = mpl.rcParams['circuits.font'][k]
    r = mpl.rcParams['circuits.scale']*0.25/3
    ax.add_patch(Circle(pos, r, zorder=zorder, edgecolor='none',
                        facecolor=color))
    if label:
        xx = 0
        yy = 0
        ha = 'center'
        va = 'center'
        if align == 'right' or 'east' in align:
            xx = 2*r
            ha = 'left'
        elif align == 'left' or 'west' in align:
            xx = -2*r
            ha = 'right'
        if align == 'above' or 'north' in align:
            yy = 2*r
            va = 'bottom'
        elif align == 'below' or 'south' in align:
            yy = -2*r
            va = 'top'
        if not 'ha' in kwargs and not 'horizontalalignment' in kwargs:
            kwargs['ha'] = ha
        if not 'va' in kwargs and not 'verticalalignment' in kwargs:
            kwargs['va'] = va
        ax.text(pos[0] + xx, pos[1] + yy, label, zorder=zorder+1, **kwargs)
    return Pos(pos[0], pos[1])

def connect(ax, nodes, lw=None, color=None, zorder=None)

Draw horizontal and vertical lines connecting circuit elements.

Parameters

ax : matplotlib axes

Axes where to draw the connections.

nodes : list of Pos or 2-tuple of floats

x and y-coordinates of positions that should be connected. If an element is None then leave a gap between the neighboring nodes. Makes only horizontal and vertical connection lines in counter-clockwise direction.

lw : float, int

Linewidth for drawing the connection lines. Defaults to circuits.linewidth rcParams settings.

color matplotlib color

Color of the connection lines.

Defaults to circuits.color rcParams settings.

zorder : int

zorder for the connection lines. Defaults to circuits.zorder rcParams settings.

Expand source code

def connect(ax, nodes, lw=None, color=None, zorder=None):
    """ Draw horizontal and vertical lines connecting circuit elements.

    Parameters
    ----------
    ax: matplotlib axes
        Axes where to draw the connections.
    nodes: list of Pos or 2-tuple of floats
        x and y-coordinates of positions that should be connected.
        If an element is `None` then leave a gap between the neighboring nodes.
        Makes only horizontal and vertical connection lines in
        counter-clockwise direction.
    lw: float, int
        Linewidth for drawing the connection lines.
        Defaults to `circuits.linewidth` rcParams settings.
    color matplotlib color
        Color of the connection lines.
        Defaults to `circuits.color` rcParams settings.
    zorder: int
        zorder for the connection lines.
        Defaults to `circuits.zorder` rcParams settings.
    """
    if lw is None:
        lw = mpl.rcParams['circuits.connectwidth']
    if color is None:
        color = mpl.rcParams['circuits.color']
    if zorder is None:
        zorder = mpl.rcParams['circuits.zorder']
    xs = []
    ys = []
    px = None
    py = None
    for n in nodes:
        if n is None:
            xs.append(np.nan)
            ys.append(np.nan)
            px = None
            py = None
        else:
            x = n[0]
            y = n[1]
            if px is None or x == px or y == py:
                xs.append(x)
                ys.append(y)
            else:
                if (x - px)*(y - py) > 0:
                    xs.extend((x, x))
                    ys.extend((py, y))
                else:
                    xs.extend((px, x))
                    ys.extend((y, y))
            px = x
            py = y
    ax.plot(xs, ys, lw=lw, color=color, zorder=zorder)

def connect_straight(ax, nodes, lw=None, color=None, zorder=None)

Draw straight lines connecting circuit elements.

Parameters

ax : matplotlib axes

Axes where to draw the connections.

nodes : list of Pos or 2-tuple of floats

x and y-coordinates of positions that should be connected. If an element is None then leave a gap between the neighboring nodes.

lw : float, int

Linewidth for drawing the connection lines. Defaults to circuits.linewidth rcParams settings.

color matplotlib color

Color of the connection lines.

Defaults to circuits.color rcParams settings.

zorder : int

zorder for the connection lines. Defaults to circuits.zorder rcParams settings.

Expand source code

def connect_straight(ax, nodes, lw=None, color=None, zorder=None):
    """ Draw straight lines connecting circuit elements.

    Parameters
    ----------
    ax: matplotlib axes
        Axes where to draw the connections.
    nodes: list of Pos or 2-tuple of floats
        x and y-coordinates of positions that should be connected.
        If an element is `None` then leave a gap between the neighboring nodes.
    lw: float, int
        Linewidth for drawing the connection lines.
        Defaults to `circuits.linewidth` rcParams settings.
    color matplotlib color
        Color of the connection lines.
        Defaults to `circuits.color` rcParams settings.
    zorder: int
        zorder for the connection lines.
        Defaults to `circuits.zorder` rcParams settings.
    """
    if lw is None:
        lw = mpl.rcParams['circuits.connectwidth']
    if color is None:
        color = mpl.rcParams['circuits.color']
    if zorder is None:
        zorder = mpl.rcParams['circuits.zorder']
    xs = []
    ys = []
    for n in nodes:
        if n is None:
            xs.append(np.nan)
            ys.append(np.nan)
        else:
            x = n[0]
            y = n[1]
            xs.append(x)
            ys.append(y)
    ax.plot(xs, ys, lw=lw, color=color, zorder=zorder)

def circuits_params(scale=None, connectwidth=None, linewidth=None, color=None, facecolor=None, alpha=None, zorder=None, font=None)

Set rc settings for circuits.

Only parameters that are not None are updated.

Parameters

scale : float

Size of circuit elements as the height of a vertical resistance in x/y coordinate units.

connectwidth : int, float

Line width of lines connecting circuit elements. Set rcParam circuits.connectwidth.

linewidth : int, float

Line width used for drawing circuit elements. Set rcParam circuits.linewidth.

color : matplotlib color

Color of the connections and circuit elements. Set rcParam circuits.color.

facecolor : matplotlib color

Face color for closed circuit elements like resistances or opamps. Set rcParam circuits.facecolor.

alpha : float

Alpha value for face color for closed circuit elements like resistances or opamps. Set rcParam circuits.alpha.

zorder : int

Zorder for all circuit elements drawn. Set rcParam circuits.zorder.

font : dict

Dictionary with font settings used for labeling circuit elements (e.g. fontsize, fontfamiliy, fontstyle, fontweight, bbox, …). Set rcParam circuits.font.

Expand source code

def circuits_params(scale=None, connectwidth=None, linewidth=None,
                    color=None, facecolor=None, alpha=None,
                    zorder=None, font=None):
    """Set rc settings for circuits.
                  
    Only parameters that are not `None` are updated.

    Parameters
    ----------
    scale: float
        Size of circuit elements as the height of a vertical resistance
        in x/y coordinate units.
    connectwidth: int, float
        Line width of lines connecting circuit elements.
        Set rcParam `circuits.connectwidth`.
    linewidth: int, float
        Line width used for drawing circuit elements.
        Set rcParam `circuits.linewidth`.
    color: matplotlib color
        Color of the connections and circuit elements.
        Set rcParam `circuits.color`.
    facecolor: matplotlib color
        Face color for closed circuit elements like resistances or opamps.
        Set rcParam `circuits.facecolor`.
    alpha: float
        Alpha value for face color for closed circuit elements like
        resistances or opamps.
        Set rcParam `circuits.alpha`.
    zorder: int
        Zorder for all circuit elements drawn.
        Set rcParam `circuits.zorder`.
    font: dict
        Dictionary with font settings used for labeling circuit elements
        (e.g. fontsize, fontfamiliy, fontstyle, fontweight, bbox, ...).
         Set rcParam `circuits.font`.
    """
    if scale is not None and 'circuits.scale' in mrc._validators:
        mpl.rcParams['circuits.scale'] = scale
    if connectwidth is not None and 'circuits.connectwidth' in mrc._validators:
        mpl.rcParams['circuits.connectwidth'] = connectwidth
    if linewidth is not None and 'circuits.linewidth' in mrc._validators:
        mpl.rcParams['circuits.linewidth'] = linewidth
    if color is not None and 'circuits.color' in mrc._validators:
        mpl.rcParams['circuits.color'] = color
    if facecolor is not None and 'circuits.facecolor' in mrc._validators:
        mpl.rcParams['circuits.facecolor'] = facecolor
    if alpha is not None and 'circuits.alpha' in mrc._validators:
        mpl.rcParams['circuits.alpha'] = alpha
    if zorder is not None and 'circuits.zorder' in mrc._validators:
        mpl.rcParams['circuits.zorder'] = zorder
    if font is not None and 'circuits.font' in mrc._validators:
        mpl.rcParams.update({'circuits.font': font})

def install_circuits()

Install circuits functions on matplotlib axes.

This function is also called automatically upon importing the module.

See Also

uninstall_circuits()

Expand source code

def install_circuits():
    """ Install circuits functions on matplotlib axes.

    This function is also called automatically upon importing the module.

    See also
    --------
    uninstall_circuits()
    """
    if not hasattr(mpl.axes.Axes, 'resistance_h'):
        mpl.axes.Axes.resistance_h = resistance_h
    if not hasattr(mpl.axes.Axes, 'resistance_v'):
        mpl.axes.Axes.resistance_v = resistance_v
    if not hasattr(mpl.axes.Axes, 'resistance'):
        mpl.axes.Axes.resistance = resistance
    if not hasattr(mpl.axes.Axes, 'capacitance_h'):
        mpl.axes.Axes.capacitance_h = capacitance_h
    if not hasattr(mpl.axes.Axes, 'capacitance_v'):
        mpl.axes.Axes.capacitance_v = capacitance_v
    if not hasattr(mpl.axes.Axes, 'battery_h'):
        mpl.axes.Axes.battery_h = battery_h
    if not hasattr(mpl.axes.Axes, 'battery_v'):
        mpl.axes.Axes.battery_v = battery_v
    if not hasattr(mpl.axes.Axes, 'ground'):
        mpl.axes.Axes.ground = ground
    if not hasattr(mpl.axes.Axes, 'opamp_l'):
        mpl.axes.Axes.opamp_l = opamp_l
    if not hasattr(mpl.axes.Axes, 'opamp_r'):
        mpl.axes.Axes.opamp_r = opamp_r
    if not hasattr(mpl.axes.Axes, 'node'):
        mpl.axes.Axes.node = node
    if not hasattr(mpl.axes.Axes, 'connect'):
        mpl.axes.Axes.connect = connect
    if not hasattr(mpl.axes.Axes, 'connect_straight'):
        mpl.axes.Axes.connect_straight = connect_straight
    # add circuits parameter to rc configuration:
    if 'circuits.scale' not in mpl.rcParams:
        mrc._validators['circuits.scale'] = mrc.validate_float
        mrc._validators['circuits.connectwidth'] = mrc.validate_float
        mrc._validators['circuits.linewidth'] = mrc.validate_float
        mrc._validators['circuits.color'] = mrc.validate_string
        mrc._validators['circuits.facecolor'] = mrc.validate_string
        mrc._validators['circuits.alpha'] = mrc.validate_float
        mrc._validators['circuits.zorder'] = mrc.validate_float
        mrc._validators['circuits.font'] = _validate_fontdict
        mpl.rcParams.update({'circuits.scale': 1,
                             'circuits.connectwidth': 1,
                             'circuits.linewidth': 2,
                             'circuits.color': 'black',
                             'circuits.facecolor': 'white',
                             'circuits.alpha': 1,
                             'circuits.zorder': 100,
                             'circuits.font': dict()})

def uninstall_circuits()

Uninstall circuits functions from matplotlib axes.

Call this code to disable anything that was installed by install_circuits().

See Also

install_circuits()

Expand source code

def uninstall_circuits():
    """ Uninstall circuits functions from matplotlib axes.

    Call this code to disable anything that was installed by `install_circuits()`.

    See also
    --------
    install_circuits()
    """
    if hasattr(mpl.axes.Axes, 'resistance_h'):
        delattr(mpl.axes.Axes, 'resistance_h')
    if hasattr(mpl.axes.Axes, 'resistance_v'):
        delattr(mpl.axes.Axes, 'resistance_v')
    if hasattr(mpl.axes.Axes, 'resistance'):
        delattr(mpl.axes.Axes, 'resistance')
    if hasattr(mpl.axes.Axes, 'capacitance_h'):
        delattr(mpl.axes.Axes, 'capacitance_h')
    if hasattr(mpl.axes.Axes, 'capacitance_v'):
        delattr(mpl.axes.Axes, 'capacitance_v')
    if hasattr(mpl.axes.Axes, 'battery_h'):
        delattr(mpl.axes.Axes, 'battery_h')
    if hasattr(mpl.axes.Axes, 'battery_v'):
        delattr(mpl.axes.Axes, 'battery_v')
    if hasattr(mpl.axes.Axes, 'ground'):
        delattr(mpl.axes.Axes, 'ground')
    if hasattr(mpl.axes.Axes, 'opamp_l'):
        delattr(mpl.axes.Axes, 'opamp_l')
    if hasattr(mpl.axes.Axes, 'opamp_r'):
        delattr(mpl.axes.Axes, 'opamp_r')
    if hasattr(mpl.axes.Axes, 'node'):
        delattr(mpl.axes.Axes, 'node')
    if hasattr(mpl.axes.Axes, 'connect'):
        delattr(mpl.axes.Axes, 'connect')
    if hasattr(mpl.axes.Axes, 'connect_straight'):
        delattr(mpl.axes.Axes, 'connect_straight')
    mrc._validators.pop('circuits.scale', None)
    mrc._validators.pop('circuits.connectwidth', None)
    mrc._validators.pop('circuits.linewidth', None)
    mrc._validators.pop('circuits.color', None)
    mrc._validators.pop('circuits.facecolor', None)
    mrc._validators.pop('circuits.alpha', None)
    mrc._validators.pop('circuits.zorder', None)
    mrc._validators.pop('circuits.font', None)

def demo()

Expand source code

def demo():
    fig, ax = plt.subplots()
    e1b, e1t = ax.battery_v((0, 1), r'$E_1$')
    r1b, r1t = ax.resistance_v((e1t[0], 3), r'$R_1$')
    c1b, c1t = ax.capacitance_v((-2, 2), r'$C_1$')
    ax.connect((e1t, r1b, None, r1t, r1t.ups(0.5), c1t, None,
                c1b, e1b.downs(0.5), e1b))
    e2l, e2r = ax.battery_h((0, -1), r'$E_2$', 'below')
    r2l, r2r = ax.resistance_h((-2, e2l.y()), r'$R_2$', 'below')
    c2l, c2r = ax.capacitance_h((-1, -3), r'$C_2$', 'below')
    ax.connect((e2l, r2r, None, r2l, r2l.lefts(0.5), c2l, None,
                c2r, e2r.rights(0.5), e2r))
    op1n, op1p, op1o, op1g = ax.opamp_l((4, 2), r'$OP1$')
    n1n = ax.node(op1n.lefts(2))
    n1p = ax.node(op1p.lefts(2))
    n1o = ax.node(op1o.rights(1))
    gnd1 = ax.ground(op1g.downs(1), r'$GND_1$')
    ax.connect((op1n, n1n))
    ax.connect((op1p, n1p))
    ax.connect((op1o, n1o))
    ax.connect((op1g, gnd1))
    op2n, op2p, op2o, op2g = ax.opamp_r((4, -2), r'$OP2$')
    n2n = ax.node(op2n.rights(1))
    n2p = ax.node(op2p.rights(1))
    n2o = ax.node(op2o.lefts(2))
    gnd2 = ax.ground(op2g.downs(1), r'$GND_2$', 'left')
    ax.connect((op2n, n2n))
    ax.connect((op2p, n2p))
    ax.connect((op2o, n2o))
    ax.connect((op2g, gnd2))
    ax.set_aspect('equal')
    plt.show()

Classes

class Pos (x, y)

x and y coordinate of a circuit element.

Expand source code

class Pos(tuple):
    """ x and y coordinate of a circuit element.
    """

    def __new__(cls, x, y):
        return tuple.__new__(cls, (x, y))

    def x(self):
        """ x coordinate of the circuit element.

        Returns
        -------
        x: float
            x-coordinate
        """
        return self[0]

    def y(self):
        """ y coordinate of the circuit element.

        Returns
        -------
        y: float
            y-coordinate
        """
        return self[1]

    def up(self, delta=1):
        """ Increment y coordinate of position of circuit element.

        Parameters
        ----------
        delta: float
            Increment in data coordinates.

        Returns
        -------
        pos: Pos
            Incremented copy of position of circuit element.
        """
        return Pos(self[0], self[1] + delta)

    def down(self, delta=1):
        """ Decrement y coordinate of position of circuit element.

        Parameters
        ----------
        delta: float
            Decrement in data coordinates.

        Returns
        -------
        pos: Pos
            Decremented copy of position of circuit element.
        """
        return Pos(self[0], self[1] - delta)

    def left(self, delta=1):
        """ Decrement x coordinate of position of circuit element.

        Parameters
        ----------
        delta: float
            Decrement in data coordinates.

        Returns
        -------
        pos: Pos
            Decremented copy of position of circuit element.
        """
        return Pos(self[0] - delta, self[1])

    def right(self, delta=1):
        """ Increment x coordinate of position of circuit element.

        Parameters
        ----------
        delta: float
            Increment in data coordinates.

        Returns
        -------
        pos: Pos
            Incremented copy of position of circuit element.
        """
        return Pos(self[0] + delta, self[1])

    def ups(self, delta=1):
        """ Increment y coordinate of position of circuit element.

        Parameters
        ----------
        delta: float
            Increment in multiples of circuits scale (rcParam `circuits.scale`).

        Returns
        -------
        pos: Pos
            Incremented copy of position of circuit element.
        """
        return Pos(self[0], self[1] + delta*mpl.rcParams['circuits.scale'])

    def downs(self, delta=1):
        """ Decrement y coordinate of position of circuit element.

        Parameters
        ----------
        delta: float
            Decrement in multiples of circuits scale (rcParam `circuits.scale`).

        Returns
        -------
        pos: Pos
            Decremented copy of position of circuit element.
        """
        return Pos(self[0], self[1] - delta*mpl.rcParams['circuits.scale'])

    def lefts(self, delta=1):
        """ Decrement x coordinate of position of circuit element.

        Parameters
        ----------
        delta: float
            Decrement in multiples of circuits scale (rcParam `circuits.scale`).

        Returns
        -------
        pos: Pos
            Decremented copy of position of circuit element.
        """
        return Pos(self[0] - delta*mpl.rcParams['circuits.scale'], self[1])

    def rights(self, delta=1):
        """ Increment x coordinate of position of circuit element.

        Parameters
        ----------
        delta: float
            Increment in multiples of circuits scale (rcParam `circuits.scale`).

        Returns
        -------
        pos: Pos
            Incremented copy of position of circuit element.
        """
        return Pos(self[0] + delta*mpl.rcParams['circuits.scale'], self[1])

Ancestors

• builtins.tuple

Methods

def x(self)

x coordinate of the circuit element.

Returns

x : float

x-coordinate

Expand source code

def x(self):
    """ x coordinate of the circuit element.

    Returns
    -------
    x: float
        x-coordinate
    """
    return self[0]

def y(self)

y coordinate of the circuit element.

Returns

y : float

y-coordinate

Expand source code

def y(self):
    """ y coordinate of the circuit element.

    Returns
    -------
    y: float
        y-coordinate
    """
    return self[1]

def up(self, delta=1)

Increment y coordinate of position of circuit element.

Parameters

delta : float

Increment in data coordinates.

Returns

pos : Pos

Incremented copy of position of circuit element.

Expand source code

def up(self, delta=1):
    """ Increment y coordinate of position of circuit element.

    Parameters
    ----------
    delta: float
        Increment in data coordinates.

    Returns
    -------
    pos: Pos
        Incremented copy of position of circuit element.
    """
    return Pos(self[0], self[1] + delta)

def down(self, delta=1)

Decrement y coordinate of position of circuit element.

Parameters

delta : float

Decrement in data coordinates.

Returns

pos : Pos

Decremented copy of position of circuit element.

Expand source code

def down(self, delta=1):
    """ Decrement y coordinate of position of circuit element.

    Parameters
    ----------
    delta: float
        Decrement in data coordinates.

    Returns
    -------
    pos: Pos
        Decremented copy of position of circuit element.
    """
    return Pos(self[0], self[1] - delta)

def left(self, delta=1)

Decrement x coordinate of position of circuit element.

Parameters

delta : float

Decrement in data coordinates.

Returns

pos : Pos

Decremented copy of position of circuit element.

Expand source code

def left(self, delta=1):
    """ Decrement x coordinate of position of circuit element.

    Parameters
    ----------
    delta: float
        Decrement in data coordinates.

    Returns
    -------
    pos: Pos
        Decremented copy of position of circuit element.
    """
    return Pos(self[0] - delta, self[1])

def right(self, delta=1)

Increment x coordinate of position of circuit element.

Parameters

delta : float

Increment in data coordinates.

Returns

pos : Pos

Incremented copy of position of circuit element.

Expand source code

def right(self, delta=1):
    """ Increment x coordinate of position of circuit element.

    Parameters
    ----------
    delta: float
        Increment in data coordinates.

    Returns
    -------
    pos: Pos
        Incremented copy of position of circuit element.
    """
    return Pos(self[0] + delta, self[1])

def ups(self, delta=1)

Increment y coordinate of position of circuit element.

Parameters

delta : float

Increment in multiples of circuits scale (rcParam circuits.scale).

Returns

pos : Pos

Incremented copy of position of circuit element.

Expand source code

def ups(self, delta=1):
    """ Increment y coordinate of position of circuit element.

    Parameters
    ----------
    delta: float
        Increment in multiples of circuits scale (rcParam `circuits.scale`).

    Returns
    -------
    pos: Pos
        Incremented copy of position of circuit element.
    """
    return Pos(self[0], self[1] + delta*mpl.rcParams['circuits.scale'])

def downs(self, delta=1)

Decrement y coordinate of position of circuit element.

Parameters

delta : float

Decrement in multiples of circuits scale (rcParam circuits.scale).

Returns

pos : Pos

Decremented copy of position of circuit element.

Expand source code

def downs(self, delta=1):
    """ Decrement y coordinate of position of circuit element.

    Parameters
    ----------
    delta: float
        Decrement in multiples of circuits scale (rcParam `circuits.scale`).

    Returns
    -------
    pos: Pos
        Decremented copy of position of circuit element.
    """
    return Pos(self[0], self[1] - delta*mpl.rcParams['circuits.scale'])

def lefts(self, delta=1)

Decrement x coordinate of position of circuit element.

Parameters

delta : float

Decrement in multiples of circuits scale (rcParam circuits.scale).

Returns

pos : Pos

Decremented copy of position of circuit element.

Expand source code

def lefts(self, delta=1):
    """ Decrement x coordinate of position of circuit element.

    Parameters
    ----------
    delta: float
        Decrement in multiples of circuits scale (rcParam `circuits.scale`).

    Returns
    -------
    pos: Pos
        Decremented copy of position of circuit element.
    """
    return Pos(self[0] - delta*mpl.rcParams['circuits.scale'], self[1])

def rights(self, delta=1)

Increment x coordinate of position of circuit element.

Parameters

delta : float

Increment in multiples of circuits scale (rcParam circuits.scale).

Returns

pos : Pos

Incremented copy of position of circuit element.

Expand source code

def rights(self, delta=1):
    """ Increment x coordinate of position of circuit element.

    Parameters
    ----------
    delta: float
        Increment in multiples of circuits scale (rcParam `circuits.scale`).

    Returns
    -------
    pos: Pos
        Incremented copy of position of circuit element.
    """
    return Pos(self[0] + delta*mpl.rcParams['circuits.scale'], self[1])