thunderfish

Detect, analyze, and plot all EOD waveforms in a short recording.

Authors

The Neuroethology-lab at the Institute of Neuroscience at the University of Tübingen:

Jan Benda
Jörg Henninger (harmonic groups)
Juan Sehuanes (best window)
Till Raab (annotation)
Liz Weerdmeester (pulse clustering)

Principles of operation

thunderfish automatically detects and analyzes all wave- and pulse-type EOD waveforms in a short recording. A short recording is typically no longer than about 30s. The recordings are made either with a fishfinder (a stick with two electrodes used to find electric fish in the field) or standardized head-tail recordings in a little tank.

A segment for further waveform analysis is identified in the recording (bestwindow module). In this segment the amplitude of the recording is largest while at the same time most stable and not clipped.
A powerspectrum of a given frequency resolution is computed (powerspectrum module) and potential EOD frequencies of wave-type fish are detected in this power spectrum based on their harmonic structure (harmonics module).
EODs of pulse-type fish are detected and clustered according to their width, amplitude, and shape (pulse module).
For each pulse and wave-type fish detected in the recording an averaged waveform is computed and its properties are analyzed (eodanalysis module)

The files generated by thunderfish on EOD waveform properties can be summarized in single files by means of the collectfish script and then analyzed and explored with the eodexplorer.

Command line arguments

thunderfish --help

returns

usage: thunderfish.py [-h] [--version] [-v] [-V] [-c] [--channel CHANNEL] [-t TIME] [-T] [-m {w,p,wp}] [-a] [-S] [-b]
                      [-l [MINFREQ]] [-p] [-M PDFFILE] [-P rtpwse] [-d PATH] [-j [JOBS]] [-s] [-z]
                      [-f {dat,ascii,csv,rtai,md,tex,html,py}] [-o OUTPATH] [-k] [-i KWARGS]
                      [file [file ...]]

Analyze EOD waveforms of weakly electric fish.

positional arguments:
  file                  name of a file with time series data of an EOD recording, may include wildcards

optional arguments:
  -h, --help            show this help message and exit
  --version             show program's version number and exit
  -v                    verbosity level. Increase by specifying -v multiple times, or like -vvv
  -V                    level for debugging plots. Increase by specifying -V multiple times, or like -VVV
  -c                    save configuration to file thunderfish.cfg after reading all configuration files
  --channel CHANNEL     channel to be analyzed (defaults to first channel, negative channel selects all channels)
  -t TIME               start time of analysis window in recording: "beginning", "center", "end", "best", or time in seconds
                        (overwrites "windowPosition" in cofiguration file)
  -T                    add start time of analysis file to output file names
  -m {w,p,wp}           extract wave "w" and/or pulse "p" fish EODs
  -a                    show all EOD waveforms in the summary plot
  -S                    plot spectra for all EOD waveforms in the summary plot
  -b                    indicate bad EODs in legend of power spectrum
  -l [MINFREQ]          logarithmic frequency axis in power spectrum with optional minimum frequency (defaults to 100 Hz)
  -p                    save output plots as pdf files
  -M PDFFILE            save all summary plots of all recordings in a multi page pdf file. Disables parallel jobs.
  -P rtpwse             save subplots as separate pdf files: r) recording with analysis window, t) data trace with detected
                        pulse fish, p) power spectrum with detected wave fish, w/W) mean EOD waveform, s/S) EOD spectrum, e/E)
                        EOD waveform and spectra, d) the default summary plot. Capital letters produce a single multipage pdf
                        containing plots of all detected fish
  -d PATH               path to raw EOD recordings needed for plotting based on analysis results
  -j [JOBS]             number of jobs run in parallel. Without argument use all CPU cores.
  -s                    save analysis results to files
  -z                    save analysis results in a single zip file
  -f {dat,ascii,csv,rtai,md,tex,html,py}
                        file format used for saving analysis results, defaults to the format specified in the configuration file
                        or "csv"
  -o OUTPATH            path where to store results and figures (defaults to current working directory)
  -k                    keep path of input file when saving analysis files, i.e. append path of input file to OUTPATH
  -i KWARGS             key-word arguments for the data loader function

version 1.9.9 by Benda-Lab (2015-2022)

examples:
- analyze the single file data.wav interactively:
  > thunderfish data.wav
- extract wavefish only:
  > thunderfish -m w data.wav
- automatically analyze all wav files in the current working directory and save analysis results and plot to files:
  > thunderfish -s -p *.wav
- analyze all wav files in the river1/ directory, use all CPUs, and write files directly to "results/":
  > thunderfish -j -s -p -o results/ river1/*.wav
- analyze all wav files in the river1/ directory and write files to "results/river1/":
  > thunderfish -s -p -o results/ -k river1/*.wav
- write configuration file:
  > thunderfish -c

Configuration file

Many parameters of the algorithms used by thunderfish can be set via a configuration file.

Generate the configuration file by executing

thunderfish -c

This first reads in all configuration files found (see below) and then writes the file thunderfish.cfg into the current working directory.

Whenever you run thunderfish it searches for configuration files in

the current working directory
the directory of each input file
the parent directories of each input file, up to three levels up.

Best practice is to move the configuration file to the root of the file tree where data files of a recording session are stored.

Use the -v switch twice to see which configuration files are loaded:

thunderfish -vv data.wav

Open the configuration file in your favourite editor and edit the settings. Each parameter is briefly explained in the comment preceding the parameter.

Important configuration parameter

The list of configuration parameter is overwhelming and most of them you do not need to touch at all. Here is a list of the few that matter (in the order as they appear in the configuration file):

frequencyResolution: this sets the nnft parameter for computing the power spectrum such to achieve the requested resolution in frequency. The longer your analysis window the smaller you can set the resultion (not smaller then the inverse analysis window).
numberPSDWindows: If larger than one then only fish that are present in all windows are reported. If you have very stationary data (from a restrained fish, not from a fishfinder) you may set this to one.
lowThresholdFactor, highThresholdFactor: play around with these numbers if not all wavefish are detected or if too many peaks are detected in the power spectrum.
mainsFreq: Set it to the frequency of your mains power supply (50 or 60 Hz) or to zero if you have hum-free recordings.
maxRelativePower: Usually, the higher the harmonics the less power it has. In order to discard signals whose power does not decay set this -10 or -20 dB.
maxGroups: Set to 1 if you know that only a single fish is in your recording.
minDataAmplitude, maxDataAmplitude: If the maximum voltage range your recording device differs from -1 to 1 (default for WAV files), set these two parameter to the limits, so that clipped recordings are detected as such.
windowSize: How much of the data should be used for analysis. If you have stationary data (from a restrained fish, not from a fishfinder) you may want to use the full recording by setting this to zero.
windowPosition: Where to place the analysis window: at the "beginning", "center", or "end" of the recording. If set to "best" (default) thunderfish searches for the most stationary data segment of the requested length. Can be overwritten from the command line with the -t argument.
pulseWidthPercentile: If low frequency pulse fish are missed then reduce this number.
eodMaxEODs: The average waveform is estimated by averaging over at maximum this number of EODs. If wavefish change their frequency then you do not want to set this number too high (10 to 100 is enough for reducing noise). If you have several fish on your recording then this number needs to be high (1000) to average away the other fish. Set it to zero in order to use all EODs in the data segment selected for analysis.
flipWaveEOD, flipPulseEOD: In case of recordings with a fishfinder you do not know the orientation of the fish relative to your electrode. That is you do not know the polarity of your recording. Setting this to auto flips the sign of the averaged EOD waveform to a standardized polarity (wave-type fish: larger peak relative to average is positive, pulse-type fish: the first of the two largest peaks is positive).
fileFormat: sets the default file format to be used for storing the analysis results.

Summary plots

By default, thunderfish simply displays the analysis results in a summary plot.

You can produce these plots either from the recording files or directly from the saved analysis results (.csv or .zip files, see next section). So to analyse some recordings and save the summary plots to pdf files in the images/ folder you call

thunderfish -p -o images data/*.wav

But this might take a while since the analysis is costly.

Alternatively you might first analyze the recordings and save the analyis results as zip files in a results/ folder:

thunderfish -j -s -z -o results data/*.wav

Afterwards, you then can quickly look at the results by calling

thunderfish -d data/ results/*.zip

and press q to flip through the plots. The -d option tells thunderfish where it finds the corresponding files with the recordings.

In the summary plots you can press

q: Close the plot window and show the next one or quit.
p: Play the analyzed section of the reording on the default audio device.
m: Play an associated voice message file (a file with the same name but -message added.
o: Switch on zoom mode. You can draw a rectangle with the mouse to zoom in.
Backspace: Zoom back.
f: Toggle full screen mode.

Notem that the coordinates under the mouse pointer are displayed as well (usually in the bottom right corner).

By default, the summary plots display at maximum four EOD waveforms with the largest amplitudes. If only a single waveform is found, then its spectrum is displayed as well. The frequencies of the power spectrum of the recording are shown on a linear scale. These behaviors can be modified by the following command line options:

-a: plot all detected EOD waveforms in summary plots.
-S: plot spectra for all displayed EOD waveforms.
-b: indicate bad EODs in the legend of the power spectrum of the recording.
-l [MINFREQ]: plot the power spectrum on a logarithmic frequency scale. The optional argument in addition allows to set the minimum frequency MINFREQ in Hertz that is displayed (defaults to 100 Hz).

The plots can alternatively be saved to pdf files via the -p option. They are named RECORDING.pdf, where RECORDING is the base name of the recording file. See next section on how to define the output folder (-o and -k options).

The summary plots of all analyzed recordings can also be stored in a single, multi-page pdf file, where the results of each recording are plotted on a separate page. For this supply a name for the pdf file via the -M option.

The various subplots of the summary plot can also be viewd separately or saved in separate pdf files. For this, use the -P option. It expects as an argument a string whose characters specify what you want to plot:

r: plot the whole recording with the analysis window indicated (saved into RECORDING-recording.pdf).
t: plot of a small section of the data trace with detected pulse fish (saved into RECORDING-trace.pdf).
p: power spectrum of the recording with detected wave fish (saved into RECORDING-psd.pdf).
w/W: annotated mean EOD waveforms (saved into RECORDING-waveforms.pdf).
s/S: spectrum of the EOD waveform (saved into RECORDING-spectrum.pdf).
e/E: Both the annotated EOD waveform and its spectrum (saved into RECORDING-eods.pdf).
d: the default summary plot (saved into RECORDING.pdf).

Capital letters produce a single multipage pdf containing the specified plots of all detected fish of a recording. For example,

thunderfish -p -P pE -d data/ -o images/ results/*.zip

produces pdf files with the power spectrum of the recording and with all the EOD waveforms together with their spectra in the folder images/. For computing the power spectrum thunderfish needs the raw data that it finds in the data/ folder.

Output pathes

Output files (plots and/or analysis results) are placed in the current working directory if no path is specified via the -o switch. If the path specified via -o does not exist it is created.

With the -k switch the pathes of the input files are appended to the output path. This allows you to analyse recordings organized in a nested directory structure in one step and write the files in the same structure. For example:

thunderfish -s -k -o analysis river1/habitatA/*.wav river1/habitatB/*.wav river2/*.wav

will store the files in

analysis/river1/habitatA/
analysis/river1/habitatB/
analysis/river2/

whereas without the -k switch all files are stored in

analysis/

To make use of all the cores of your CPU apply the -j switch.

Analysis results

With the -s switch analysis results are saved to files and no interactive output plots are generated.

The many output files (see below) can be combined into a single zip archive (one per recording) with the -z option.

The following files are generated:

RECORDING-CHANNEL-TIME-eodwaveform-N.EXT: averaged EOD waveform
RECORDING-CHANNEL-TIME-waveeodfs.EXT: list of all detected EOD frequencies and powers of wave-type fish
RECORDING-CHANNEL-TIME-wavefish.EXT: list of properties of good EODs of wave-type fish
RECORDING-CHANNEL-TIME-wavespectrum-N.EXT: for each wave-type fish the Fourier spectrum
RECORDING-CHANNEL-TIME-pulsefish.EXT: list of properties of good EODs of pulse-type fish
RECORDING-CHANNEL-TIME-pulsephases-N.EXT: for each pulse-type fish properties of EOD phases
RECORDING-CHANNEL-TIME-pulsegaussians-N.EXT: for each pulse-type fish properties of Gaussians fitting the EOD phases
RECORDING-CHANNEL-TIME-pulsetimes-N.EXT: for each pulse-type fish the time points of detected EODs
RECORDING-CHANNEL-TIME-pulsespectrum-N.EXT: for each pulse-type fish the power spectrum of a single pulse

Filenames are composed of the basename of the input file (RECORDING). In case the input files contain more than a single channel channel specification is appended (CH), a 'c' followed by the channel number. In case the start time of the analysis window was requested to be saved into the file name (-T option), this start time is added to the file name (TIME) as an 't' followed by the start time floored to integer seconds, and an 's'. Fish detected in the recordings are numbered, starting with 0 (N). The file extension depends on the chosen file format (EXT). The following sections describe the content of the generated files.

RECORDING-CHANNEL-TIME-eodwaveform-N.EXT

For each fish the average waveform with standard error and fit.

time	mean	sem	fit	tailfit
ms	a.u.	a.u.	a.u.	a.u.
-1.750	0.000183971	0.000355154	-0.00000	-
-1.719	0.000105037	0.000355562	-0.00000	-
-1.688	0.000158089	0.000353294	-0.00000	-
-1.656	6.47331e-05	0.000356885	-0.00000	-

The columns contain:

time Time in milliseconds.
mean Averaged waveform in the unit of the input data.
sem Corresponding standard error of the mean.
fit A fit to the averaged waveform. In case of a wave fish this is a Fourier series, for pulse fish it is a sum of Gaussians.
tailfit For pulse fish an exponential fit to the tail of the last EOD phase.

RECORDING-CHANNEL-TIME-waveeodfs.EXT

List of all detected EOD frequencies and powers of wave-type fish. These might be more than listed in RECORDING-CHANNEL-TIME-wavefish.EXT.

index	EODf	datapower
-	Hz	dB
1	111.33	-33.35
2	132.81	-37.86
0	580.08	-22.01
3	608.89	-45.45

The columns contain:

index Index of the fish (the number that is also used to number the files).
EODf EOD frequency in Hertz.
datapower Power of this EOD in decibel (sum over all peaks in the power spectrum of the recording).

RECORDING-CHANNEL-TIME-wavefish.EXT

Fundamental EOD frequency and other properties of each wave-type fish detected in the recording.

recording						waveform													timing
twin	window	winclipped	samplerate	nfft	dfreq	index	EODf	p-p-amplitude	power	datapower	thd	dbdiff	maxdb	noise	rmserror	clipped	flipped	n	ncrossings	peakwidth	troughwidth	minwidth	leftpeak	rightpeak	lefttrough	righttrough	p-p-distance	min-p-p-distance	relpeakampl
s	s	%	kHz	-	Hz	-	Hz	a.u.	dB	dB	%	dB	dB	%	%	%	-	-	-	%	%	%	%	%	%	%	%	%	%
4.25	8.00	0.00	32.000	131072	0.24	0	580.08	0.22755	-21.28	-19.05	149.81	2.93	-9.22	0.3	0.36	0.0	0	3300	1	76.15	23.85	23.85	69.12	7.03	11.10	12.75	18.13	18.13	75.73
4.25	8.00	0.00	32.000	131072	0.24	1	111.08	0.05387	-31.84	-30.09	69.07	4.12	-30.74	4.5	0.66	0.0	0	886	2	58.56	41.44	41.44	18.77	39.79	19.92	21.52	59.71	40.29	58.70
4.25	8.00	0.00	32.000	131072	0.24	2	133.06	0.02668	-37.91	-33.92	62.16	5.93	-33.64	8.4	0.45	0.0	0	1061	2	42.13	57.87	42.13	20.90	21.23	19.93	37.94	41.16	41.16	57.90
4.25	8.00	0.00	32.000	131072	0.24	3	608.64	0.01460	-44.82	-40.98	120.54	4.91	-22.21	7.2	0.41	0.0	0	4866	1	69.73	30.27	30.27	54.20	15.52	11.10	19.17	26.63	26.63	63.59
4.25	8.00	0.00	32.000	131072	0.24	4	1979.49	0.00177	-61.18	-58.72	58.05	13.10	-24.18	33.0	2.08	0.0	0	15833	2	53.94	46.06	46.06	22.94	31.00	24.67	21.38	55.67	44.33	56.82

The columns contain:

twin Start time of the analysis window in the recording in seconds.
window Duration of the analysis window in seconds.
winclipped: Fraction of analysis window that is clipped.
samplerate: Sampling rate of the recording.
nfft: Number of samples used for FFT to compute power spectrum.
dfreq: Frequency resolution of power spectrum.
index Index of the fish (the number that is also used to number the files).
EODf EOD frequency in Hertz.
p-p-amplitude Peak-to-peak amplitude of the extracted waveform in the units of the input data.
power Power of the extracted EOD waveform, i.e. sum of the squared Fourier amplitudes, in decibel.
datapower Power of the EOD waveform from the spectrum of the original data in decibel.
thd: Total harmonic distortion, i.e. square root of sum of amplitudes squared of harmonics relative to amplitude of fundamental.
dbdiff Smoothness of power spectrum as standard deviation of differences in decibel power.
maxdb Maximum power of higher harmonics relative to peak power in decibel.
noise Root-mean-squared standard error of the averaged EOD waveform relative to the peak-to_peak amplitude in percent.
rmserror Root-mean-squared difference between the averaged EOD waveform and the fit of the Fourier series relative to the peak-to_peak amplitude in percent.
clipped Percentage of recording that is clipped.
flipped Whether the waveform was flipped.
n Number of EODs used for computing the averaged EOD waveform.
ncrossings Number of zero crossing per EOD period.
peakwidth Width of the peak at the averaged amplitude relative to EOD period.
troughwidth Width of the trough at the averaged amplitude relative to EOD period.
minwidth: peakwidth or troughwidth, whichever is smaller.
leftpeak Time from positive zero crossing to peak relative to EOD period.
rightpeak Time from peak to negative zero crossing relative to EOD period.
lefttrough Time from negative zero crossing to trough relative to EOD period.
righttrough Time from trough to positive zero crossing relative to EOD period.
p-p-distance Time between peak and trough relative to EOD period.
min-p-p-distance: p-p-distance or EOD period minus p-p-distance, whichever is smaller, relative to EOD period.
relpeakampl Amplitude of peak or trough, whichever is larger, relative to p-p amplitude.

RECORDING-CHANNEL-TIME-wavespectrum-N.EXT

The parameter of the Fourier series fitted to the waveform of a wave-type fish.

harmonics	frequency	amplitude	relampl	relpower	phase	datapower
-	Hz	a.u.	%	dB	rad	a.u.^2/Hz
0	728.16	0.32610	100.00	0.00	0.0000	1.0137e-01
1	1456.32	0.22146	67.91	-3.36	2.4706	4.1881e-02
2	2184.48	0.03215	9.86	-20.12	-1.9333	7.6623e-04
3	2912.63	0.03733	11.45	-18.83	-0.6807	8.6311e-04
4	3640.79	0.02039	6.25	-24.08	3.0997	2.3089e-04

The columns contain:

harmonics Index of the harmonics. The first one with index 0 is the fundamental frequency.
frequency Frequency of the harmonics in Hertz.
amplitude Amplitude of each harmonics obtained by fitting a Fourier series to the data in the unit of the input data.
relampl Amplitude of each harmonics relative to the amplitude of the fundamental in percent.
relpower Power of each harmonics relative to fundamental in decibel.
phase Phase of each harmonics obtained by fitting a Fourier series to the data in radians ranging from 0 to 2 pi.
datapower Power spectral density of the harmonics from the original power spectrum of the data.

RECORDING-CHANNEL-TIME-pulsefish.EXT

Properties of each pulse-type fish detected in the recording.

recording						waveform																															spectrum
twin	window	winclipped	samplerate	nfft	dfreq	index	n	EODf	period	aoffs	pos-ampl	neg-ampl	max-ampl	p-p-amplitude	p-p-dist	noise	rmserror	clipped	flipped	startendthresh	peakthresh	tstart	tend	width	totalarea	pos-area	neg-area	polaritybalance	median	quartile1	quartile3	iq-range	tau	taustart	firstphase	lastphase	peakfreq	peakenergy	troughfreq	troughenergy	energyatt5	energyatt50	lowcutoff	highcutoff
s	s	%	kHz	-	Hz	-	-	Hz	ms	a.u.	a.u.	a.u.	a.u.	a.u.	ms	%	%	%	-	%	%	ms	ms	ms	a.u.*ms	%	%	%	ms	ms	ms	ms	ms	ms	-	-	Hz	a.u.^2s/Hz	Hz	a.u.^2s/Hz	dB	dB	Hz	Hz
4.00	8.00	0.00	32.000	131072	0.24	0	237	32.23	31.03	-0.00369	0.26582	0.21891	0.26582	0.48473	0.250	0.09	0.82	0.00	0	1.20	0.60	-0.312	0.938	-1.250	0.1194	51.90	48.10	3.80	0.094	-0.031	0.312	0.344	0.087	0.406	1	2	1123.05	1.4e-08	0.00	1e-10	-21.44	-19.89	152.34	1857.42

The columns contain:

twin Start time of the analysis window in the recording in seconds.
window Duration of the analysis window in seconds.
winclipped: Fraction of analysis window that is clipped.
samplerate: Sampling rate of the recording.
nfft: Number of samples used for FFT to compute power spectrum.
dfreq: Frequency resolution of power spectrum.
index Index of the fish (the number that is also used to number the files).
n Number of EODs used for computing the averaged EOD waveform.
EODf EOD frequency in Hertz.
period Period between two pulses (1/EODf) in milliseconds.
aoffs Offset that was subtracted from the average EOD waveform.
pos-ampl Amplitude of the largest phase (P1 phase) in the units of the input data.
neg-ampl Amplitude of the largest trough in the units of the input data.
max-ampl Maximum of largest peak or trough amplitude in the units of the input data.
p-p-amplitude Peak-to-peak amplitude in the units of the input data.
p-p-dist: Distance between minimum and maximum phase in milliseconds.
noise Average standard error of the averaged EOD waveform relative to the peak-to_peak amplitude in percent.
rmserror: Root-mean-square error between fit with sum of Gaussians and EOD waveform relative to the p-p amplitude. Infinity if fit failed.
clipped Percentage of recording that is clipped.
flipped Whether the waveform was flipped.
startendthresh The actually used threshold for start and end time as a fraction of the p-p amplitude in percent.
peakthresh The actually used threshold for detecting peaks and troughs time as a fraction of the p-p amplitude in percent.
tstart Time where the pulse starts relative to P1 in milliseconds.
tend Time where the pulse ends relative to P1 in milliseconds.
width Total width of the pulse in milliseconds.
totalarea Sum of areas under positive and negative phases.
pos-area Area under positive phases relative to total area.
neg-area Area under negative phases relative to total area.
polaritybalance Contrast between areas under positive and negative phases.
median Median of the distribution of the absolute EOD waveform.
quartile1 First quartile of the distribution of the absolute EOD waveform.
quartile3 Third quartile of the distribution of the absolute EOD waveform.
iq-range Inter-quartile range of the distribution of the absolute EOD waveform.
tau Time constant of the exponential decay of the tail of the pulse in milliseconds.
firstphase Index of the first phase in the pulse (i.e. -1 for P-1).
lastphase Index of the last phase in the pulse (i.e. 3 for P3).
peakfreq Frequency at the peak energy of the single pulse spectrum in Hertz.
peakenergy Peak energy of the single pulse spectrum.
troughfreq Frequency at trough before peak in Hertz.
troughenergy Energy of trough before peak in x^2 s/Hz.
energyatt5 Attenuation of average energy below 5 Hz relative to peak energy in decibel.
energyatt50 Attenuation of average energy below 50 Hz relative to peak energy in decibel.
lowcutoff Frequency at which the energy reached half of the peak energy relative to the DC energy in Hertz.
high_cutoff: 3dB roll-off frequency in Hertz.

RECORDING-CHANNEL-TIME-pulsephases-N.EXT

Properties of phases of a pulse-type fish's EOD.

P	time	amplitude	relampl	width	area	relarea
-	ms	a.u.	%	ms	a.u.*ms	%
1	0.000	0.26548	100.00	0.225	0.0616	50.76
2	0.250	-0.21925	-82.59	0.221	-0.0598	-49.24

The columns contain:

P Name of the phase. Phases are numbered sequentially. P1 is the largest phase with positive amplitude.
time Time of the phase's peak/trough relative to P1 in milliseconds.
amplitude Amplitude of the phase in the unit of the input data.
relampl Amplitude of the phase relative to the amplitude of P1 in percent.
width Width of the phase at half height in milliseconds.
area Area under the phase.
relaarea Area of the phase relative to total area in percent.

RECORDING-CHANNEL-TIME-pulsegaussians-N.EXT

For each pulse-type fish properties of Gaussians fitting the EOD phases.

times	amplitudes	stdevs
ms	a.u.	ms
0.058	0.58302	0.128
0.162	-0.47997	0.148

The columns contain:

times Position of each Gaussian
amplitudes Amplitude of each Gaussian
stdevs Standard deviation of each Gaussian

RECORDING-CHANNEL-TIME-pulsetimes-N.EXT

Time points of detected pulse-type EODs.

time
s
0.1043
0.1353
0.1662
0.1971
0.2279
0.2589
0.2898
0.3207

The columns contain:

The times of pulse-type EODs in seconds.

RECORDING-CHANNEL-TIME-pulsespectrum-N.EXT

The energy spectrum of a single EOD pulse of a pulse-type fish:

frequency	energy	gaussian
Hz	a.u.^2s/Hz	a.u.^2s/Hz
0.00	9.9955e-11	1.0662e-10
0.98	1.0000e-10	1.0664e-10
1.95	1.0016e-10	1.0673e-10
2.93	1.0041e-10	1.0687e-10
3.91	1.0076e-10	1.0707e-10
4.88	1.0121e-10	1.0733e-10

The columns contain:

frequency Frequency in Hertz.
energy Energy spectral density in x^2 s/Hz.
gaussian Energy spectral density of the fitted sum of Gaussians in x^2 s/Hz.