API reference¶

fitting module¶

Set of function to fit a raw data.

spikelib.fitting.fit_temp_sta(temporal_sta, time, fit_time, tau1=None, tau2=None, amp1=None, amp2=None, min_time=None, max_time=None, min_amp=-1, max_amp=1, max_n=20)[source]¶

Fit the temporal integration of the sta.

Use the difference of two cascades of low-pass filters to fit the raw temporal integration of STA. It uses the time before of the spike to compute the fitting.

Parameters:

temporal_sta (ndarray) – array with the raw temporal integration of the sta.
time (ndarray) – array with the time of the raw temporal integration.
fit_time (ndarray) – array with the time of fitting curve.
tau1 (float default:None) – estimated time for positive peak of temporal integration
tau2 (float default:None) – estimated time for negative peak of temporal integration
amp1 (float default:None) – estimated amplitude for positive peak of temporal integration
amp2 (float default:None) – estimated amplitude for negative peak of temporal integration
min_time (float default:None) – minimum time to fit tau1 or tau2
max_time (float default:None) – maximum time to fit tau1 or tau2
min_amp (float default:-1) – minimum amplitude to fit amp1 or amp2
max_amp (float default:1) – minimum amplitude to fit amp1 or amp2
max_n= (float default:20) – maximum order of a model to fit

Returns:

fit_parameters (lmfit.Params.params) – parameters of the fitting for two_cascades model
fit_temp (ndarray) – array with the values of the fitting using fit_time

spikelib.fitting.gaussian2d(xy, amp, x0, y0, sigma_x, sigma_y, theta, offset, revel=True)[source]¶

Make a two dimentional gaussian array.

Parameters:	xy (tuple (x, y)) – a meshgrid matrix of x and y axis. amplitude (float) – maximum amplitude of gaussian function x0 (float) – value where gaussian function has maximum value on x axis. y0 (float) – value where gaussian function has maximum value on y axis. sigma_x (float) – Standard deviation on x axis sigma_y (float) – Standard deviation on y axis theta (float) – rotation on x axis counterclockwise, in [radians] offset (flaot) – offset value for every point in array. revel (bool) – If revel is True, array is trnsformed to a vector.
Returns:
Return type:	Array o vector with the values od a 2 dimentional gaussian function.

Examples

>>> import numpy as np
>>> import matplotlib.pyplot as plt
>>> from spikelib.fitting import gaussian2d

>>> y_size, x_size = (35, 30)
>>> xy = np.meshgrid(np.linspace(0, x_size - 1, x_size),
                     np.linspace(0, y_size - 1, y_size),)
>>> arr = gaussian2d(xy=xy, amp=10, x0=12, y0=22, sigma_x=1.5,
                     sigma_y=3.5, theta=np.pi/4, offset=0)
>>> plt.pcolor(arr.reshape(y_size, x_size))
>>> plt.show()

spikelib.fitting.two_cascades(params, time)[source]¶

Model for temporal integration of sta.

This function return the model of the difference of two cascades of low-pass filters for temporal integration of spike triggered average (sta). It was propouse by Chichilnisky and Kalmar in ‘Functional Asymmetries In ON and OFF Ganglion Cells Of Primate Retina’.

function

Parameters:	params (dict or lmfit.Params.params) – The dictionary has 5 element for each parameter of model, ‘amp1’, ‘amp2’, ‘tau1’, ‘tau2’, ‘n’ time (ndarray) – Array with the time to compute the model.
Returns:	model – return values of the function for each element in time array
Return type:	ndarray

spikelib.fitting.two_cascades_min(params, x, raw_data)[source]¶: Difference of two cascades to minimize.

io module¶

Set of tools to manipulate input and output files.

spikelib.io.load_matstim(filepath, matvar='stim')[source]¶

Get checkerboard stim from .mat file.

Read checkerboard stimulus generate by matlab and transpose dimesion to make compatible with numpy convencion of multidimentional array. The stimulus must have 4 dimension, nframe, yblock, xbock, nchannels.

Parameters:	filepath (str) – relative or full path of matlab file. var (str default: 'stim') – name of stim variable in mat file
Returns:	stim – 4D array stimulus with the Numpy convention for dimensions (frame,y,x,channel).
Return type:	ndarray

Notes

scipy.io.loadmat read matfile in mantain the matlab axis order to access array, ej. shape (y,x,channel,frame) = (35,35,3,72000) and python should be (frame,y,x,channel) = (72000,35,35,3), for this reason the output file keep python format. https://eli.thegreenplace.net/2015/memory-layout-of-multi-dimensional-arrays/ http://scikit-image.org/docs/dev/user_guide/numpy_images.html

spikelib.io.load_spk_hdf5(filepath, group, datasets=None)[source]¶

Get spiketimes from hdf5 file.

Read HDF5 file and get all spike inside a group

Parameters:	filepath (str) – relative or full path of hdf5 file. group (str) – name of the group where timestams are datasets (list) – list of a specifict name of datasets in the group
Returns:	spks – dictionary with timestams
Return type:	dic

spikelib.io.load_spk_txt()[source]¶

spikelib.io.load_stim(filepath, normed=True, channel='g', dataset='checkerboard')[source]¶

Get checkerboard stim from hdf5 file.

Read checkerboard stimulus from hdf5 file. It file was obtained from load_matstim() function and sava to a hdf5 file. The stimulus must has 4 dimension, nframe, yblock, xbock, nchannels.

Parameters:	filepath (str) – relative or full path of hdf5 file. normed (bool default: True) – Normalize stimulus between -1 and 1. channel ({'r', 'g', 'b'}) – stimulus has 3 channels, ‘r’, ‘g’ and ‘b’. Set one of these to retrive stim intensity. dataset (str default: 'checkerboard') – name of stim dataset in hdf5 file
Returns:	stim – 3D array stimulus with the Numpy convention for dimensions.
Return type:	ndarray

spikelib.io.load_stim_multi(filepath, normed=True, channel='g', dataset='checkerboard')[source]¶

Get checkerboard stim from hdf5 file to run multiprocessing sta.

Read checkerboard stimulus generate by matlab and transpose dimesion to make compatible with numpy convencion of multidimentional array. The stimulus must have 4 dimension, nframe, yblock, xbock, nchannels.

Parameters:

filepath (str) – relative or full path of hdf5 file.
normed (bool default: True) – Normalize stimulus between -1 and 1.
channel ({'r', 'g', 'b'}) – stimulus has 3 channels, ‘r’, ‘g’ and ‘b’. Set one of these to retrive stim intensity.
dataset (str default: 'checkerboard') – name of stim dataset in hdf5 file

Returns:

stim (RawArray) – 3D array stimulus with the Numpy convention for dimensions.
stim_shape (tuple)

models module¶

Set of lineal and no lineal neuron model.

For example Spike Triggered Average (STA) is a algorithm to compute a lineal filter to estimate receptive field of a cell.

spikelib.models.init_multi_sta(stim, stim_shape)[source]¶: Set stim array to a global variable.

spikelib.models.multi_sta(spiketimes, stim_time, nsamples_before=30, nsamples_after=0)[source]¶

Compute the Spike Triggered Average for a cell.

Parameters:

spiketimes (tuple) – tuple(name, spiketimes) to compute STA
stim_time (array_like) – array with start time of each frame of stim
nsamples_before (int) – Number of samples to include in the STA before the spike
nsamples_after (int) – Number of samples to include in the STA after the spike (default: 0)

Returns:

unit_name (str) – name of the unit
sta_array (array_like) – STA array

spikelib.models.run_multi_sta(stim_path, stim_time, spiketimes, nsamples_before=30, nsamples_after=0, normed_stim=True, channel_stim='g')[source]¶

Run sta in multiprocessing.

Parameters:	stim_path (str) – file of the stim stim_time (array_like) – times of start and end of stim spiketimes (dict) – spiketimes to compute sta
Returns:	stats – return a list of tuple with unit_name and sta_array
Return type:	list of tuple

spikelib.models.sta(stim, stim_time, spikes, nsamples_before=30, nsamples_after=0)[source]¶

Compute a spike-triggered average.

Parameters:	stim (array_like) – A spatiotemporal or temporal stimulus array, where time is the first dimension. stim_time (array_like) – The time array corresponding to the start of each frame in the stimulus. spikes (array_like) – A list or array of spike times nsamples_before (int) – Number of samples to include in the STA before the spike, defaults: 30. nsamples_after (int) – Number of samples to include in the STA after the spike, efaults: 0
Returns:	sta – The spatiotemporal spike-triggered average.
Return type:	array_like

References

A simple white noise analysis of neuronal light responses. E J Chichilnisky

spikelib.models.ste(stim, stim_time, spikes, nsamples_before=30, nsamples_after=0)[source]¶

Get all windows of stimulis triggered by a spike.

This function create a iterator to get a set of stimulus for a spike.

Parameters:	time_stim (array_like) – The time array corresponding to the start of each frame in the stimulus. stimulus (array_like) – A spatiotemporal or temporal stimulus array, where time is the first dimension. spikes (array_like) – A list or ndarray of spike times. nsamples_before (int) – Number of samples to include in the STE before the spike, defaults: 30. nsamples_after (int) – Number of samples to include in the STE after the spike, defaults: 0.
Returns:	ste – A generator that yields samples from the spike-triggered ensemble.
Return type:	generator

Notes

The spike-triggered ensemble (STE) is the set of all stimuli immediately surrounding a spike. If the full stimulus distribution is p(s), the STE is p(s | spike).

preprocessing module¶

spiketools module¶

Set of functions to work with spike times.

spikelib.spiketools.bias_index(fr_max_on, fr_max_off, thr=0.65)[source]¶

Get the bias index from a On Off response.

The bias index compare the response to 2 differente stimuli, ON and OFF, and classify between, ON, OFF and ONOFF response. .. math:: bias_index = \frac{ON_{max}-OFF_{max}}{ON_{max}+OFF_{max}}

Parameters:

fr_max_on (float) – firing rate maximum for On response
fr_max_off (float) – firing rate maximum for Off response
thr (float) – threshold to split On, Off and On-Off groups

Returns:

bias_index (float) – number between -1 and 1.
response_type (int) –

clasification for type of response

0: null response 1: On response 2: Off response 3: On-Off response

See also

est_pdf()

spikelib.spiketools.chunk_spikes(spikes, start, end)[source]¶

Get a subset of spike between start and end time.

Parameters:	spikes (array_like) – array with timestams of a cell start (float) – time of start the chunk end (float) – time of end the chunk
Returns:	chunk – subset of spikes
Return type:	array_like

See also

get_trials(), flatten_trials()

spikelib.spiketools.decay_time(response, time, peaktime, max_resp, decrease_factor=2.718281828459045)[source]¶

Get the time of the response dalay to dacay.

Dacay time is the time that the response take to dacay $n$ factor to the max response.

Parameters:	response (array_like) – psth or estimated firingrate time (array_like) – time of response peaktime (float) – time where is the max response max_resp (int) – value of the max response decrease_factor (float) – number of time that maximum response should dacay to get decay_time
Returns:	resp_index – value between 0 to 1, where 0 mean that the response don’t change to the stimulus and 1 mean the previous response was 0 and response was max.
Return type:	float

See also

est_pdf()

spikelib.spiketools.est_pdf(trails, time, bandwidth=0.02, norm_factor=1)[source]¶

Estimate the probability density function from spike.

This function estimate the pdf of a cell to get a instantaneous firing rates.

Parameters:	spikes (list of array_like) – List with all spike times in each trial time (array_like) – Array of time points where pdf will be estimate.
Returns:	estimated pdf from trails
Return type:	array_like

spikelib.spiketools.flatten_trials(trials)[source]¶

Put spike times from different trial in a 1D array.

Parameters:	trials (list of array_like) – list with all spike in each trial
Returns:	1D array with all spike together
Return type:	array_like

See also

chunk_spikes(), get_trials()

spikelib.spiketools.get_features_flash(response, time_resp, bound, resp_thr=0.3, bias_thr=0.65, ri_thr=0.3, fpeak_thr=0.3, fpeak_min_dist=10, ri_span=0.1, sust_time=0.4, decrease_factor=2.718281828459045)[source]¶

Get temporal characteristic of flash response.

Parameters:

response (array_like) – psth or estimated firingrate
array (time_resp,) – time of response in seg
bound (tuple) – (start_time_on, end_time_on, start_time_off, end_time_off)
resp_thr (float default=0.3) – threshold to define if response is valid
bias_thr (float default=0.65) – threshold for bias index
ri_thr (float default=0.3) – threshold for response index
fpeak_thr (float default=0.3) – threshold for find peak response
fpeak_min_dist (int default=10) – number of point minimum to detect peak response
ri_span=0.1 (float default=0.1) – windows time to compute response index in seg
sust_time (float default=0.4) – windows time to compute sutained index in seg
decrease_factor (float default=np.e) – feaactor to get decrease time

Returns:

flash_type (int) – Flash clasification, 0, 1, 2 or 3 that represent Null, ON, OFF and ONOFF.
flash_char (array_like) – Array with the follow paramiters: [latency_on, latency_off, bias_idx, decay_on, decay_off, resp_index_on, resp_index_off, sust_index_on, sust_index_off, fr_max_on, fr_max_off]

spikelib.spiketools.get_trials(spikes, start_trials, end_trials, offset=0)[source]¶

Get a list of spiketime for each trails.

Search spike times in set of period of time(s) defined in start_trials and end_trails and return a list of spiketimes for each trails and set the start time to 0 for each trail.

Parameters:	spikes (array_like) – Array of all spike times. start_trials (array_like) – Set of start time for each trail. end_trials (array_like) – Set of end time for each trail. offset (float, optional) – offset allow move the reference of start time, default is 0.
Returns:	List of array of all spikes for each trial.
Return type:	list

See also

chunk_spikes(), flatten_trials()

spikelib.spiketools.response_index(response, prev_response, ri_span, max_resp=None)[source]¶

Get the response index.

The response index compare the response to a stimulus against previous response to the stimulus. It measure allow cuantify how much to change the response to a stimulus. .. math:: resp_index = frac{resp_{max}-avg_{prev_resp}}{resp_{max}+avg_{prev_resp}}

Parameters:	response (array_like) – response for analysis prev_response (array_like) – previous response for analysis ri_span (int) – number of de points to analize in response and prev_resp max_resp (float) – peak of response
Returns:	resp_index – value between 0 to 1, where 0 mean that the response don’t change to the stimulus and 1 mean the previous response was 0 and response was max.
Return type:	float

See also

est_pdf()

spikelib.spiketools.sustain_index(response)[source]¶

Get the sustained index.

Sustained Index (SI) measure if the response is transient or sustained, where 0 is completly sustained and 1 is completly transient.

Parameters:	response (array_like) – PSTH or estimated response array of a cell in a specific estimulation.
Returns:	sust_index – index between 0 and 1.
Return type:	float

See also

est_pdf()

stimtools module¶

Tools to manipulate stumulus.

spikelib.stimtools.correct_checkerboard(stimpath, syncpath, repeatedpath, outputpath, matvar='stim', output_group='/', output_dataset='checkerboard')[source]¶

Create a new stimulus with all repeated frames.

Take a checkerboar stimulus and add all repeated frame found in a experiment and create a new stim file.

Parameters:	stimpath (str) – path to original stim file (.mat). syncpath (str) – path to the syncronization file with start and end time for checkerboard (txt format). repeatedpath (str) – path to file with all repeated times of experiment (txt format). outputpath (str) – path to save stim to hdf5 file.

Notes

scipy.io.loadmat read matfile in mantain the matlab axis order to access array, ej. shape (y,x,channel,frame) = (35,35,3,72000) and python should be (frame,y,x,channel) = (72000,35,35,3), for this reason the output file keep python format. https://eli.thegreenplace.net/2015/memory-layout-of-multi-dimensional-arrays/ http://scikit-image.org/docs/dev/user_guide/numpy_images.html

utils module¶

spikelib utilities.

spikelib.utils.check_directory(inputfolder)[source]¶

Check if exist the directory, else make a new folder.

If the directory doesn’t exist then this directory is create.

Parameters:	inputfolder (str) – path of directory

Examples

>>> checkDirectory('../myFolder')

spikelib.utils.check_groups(fdata, groups)[source]¶

Review if a list of groups exist in a hdf file.

Parameters:	fdata (object) – h5py object to check if a list of group exist groups (list of str) – list of group name to check

spikelib.utils.clean_directory(inputfolder)[source]¶

Delete all files and drectories in input directory.

If the directory doesn’t exist then this directory is create.

Parameters:	inputfolder (str) – path of directory

Examples

>>> from mealib.utils import clean_directory
>>> clean_directory('../myinputfolder')

spikelib.utils.datasets_to_array(fgroup)[source]¶

Transform all datasets in a group to an array.

Parameters:	fgroup (object) – h5py object to retrive all dataset inside of it
Returns:	ds_array (array_like) – NxM array, where N if the number of dataset and M is the lenght of each dataset names (list of str) – list of names for each row in ds_array

Examples

>>> with h5py.File(fdata) as data:
>>>    array, keys = datasets_to_array(data[group])
>>> array.shape
(889,7)

visualizations module¶

Set of tools for visualization.

spikelib.visualizations.plot_sta(sta_array, name='')[source]¶

Get a plot with all frame of the STA.

Parameters:

sta_array (array_like) – STA array
name (str) – name of unit

Returns:

fig (figure object) – current figure of the plot
ax (axis object) – axis with psth

spikelib.visualizations.psth(spks, ax=None, **kwargs)[source]¶

Draw psth for spikes.

Parameters:

spks (array_like) – 1D array with spiketimes for each trial
**kwargs – kwargs of axis of matplotlib

Returns:

fig (figure object) – current figure of the plot
ax (axis object) – axis with psth

spikelib.visualizations.raster(trials, ax=None, **kwargs)[source]¶

Draw raster for a cell.

Parameters:

trials (list of array_like or numpy obj) – list with spiketimes for each trial
**kwargs – kwargs of axis of matplotlib

Returns:

fig (figure object) – current figure of the plot
ax (axis object) – axis with raster

Module contents¶

spikelib.

A Python package to analyse neuronal activity from spiketimes

Modules¶

fitting - Models of neuronal behaviour. io - Tools for manupulate Input/Output files. models - Methods of linear and no lineal filters preprocessing - Classes to processes syncronization times. spiketools - Tools for manipulating spike trains. stimtools - Tools for manipulating stimuli. utils - General functions for check folder, groups, etc. visualizations - Tools for plotting, psth, raster, receptive fields, etc.

For more information, see the accompanying README.md