ObjSim/python/objsimpy/stim/pulsegen.py

# -*- coding: utf-8 -*-
'''
Created on 25.06.2015

@author: frank
'''

def create_pulse_times(start, n, duration, period):
    return reduce(lambda a, b: a+b, 
                  [[start+i*period, start+i*period+duration] 
                   for i in range(n)])
                  
def create_pulse_gen_dict(duration=2., period=10., amplitude=1000., n=10, start=10.):
    assert period >= duration
    pulse_times = [0.,] + create_pulse_times(start, n, duration, period)
    pulse_values = [0.,] + [amplitude, 0.]*n         
    return {'amplitude_times': pulse_times, 'amplitude_values': pulse_values}

def create_burst_gen_dict(duration=2., 
                          n_spikes=5, 
                          spike_frequency=200., 
                          period=500., 
                          amplitude=1000., 
                          n=5, start=10.,
                          start_spike_amplitude=0.,
                          start_spike_time=5.,
                          start_spike_duration=2.):
    spike_period = 1000./spike_frequency
    single_burst_duration = spike_period*n_spikes
    assert duration < single_burst_duration    
    assert period >= single_burst_duration
    
    pulse_times = reduce(lambda a, b: a+b, [create_pulse_times(start+i*period, n_spikes, duration, spike_period) 
                                                   for i in range(n)])    
    pulse_values = [amplitude, 0.]*n*n_spikes

    pulse_times.insert(0, 0.)
    pulse_values.insert(0, 0.)
    if start_spike_amplitude > 0.:
        pulse_times.insert(1, start_spike_time)
        pulse_values.insert(1, start_spike_amplitude)
        pulse_times.insert(2, start_spike_time+start_spike_duration)
        pulse_values.insert(2, 0.)
        
    return {'amplitude_times': pulse_times, 'amplitude_values': pulse_values}

if __name__=='__main__':
    import pylab as plt
    p = create_pulse_gen_dict()
    plt.plot(p['amplitude_times'], p['amplitude_values'], '.-')
    plt.title("simple regular pulses")
    
    plt.figure()
    p = create_burst_gen_dict(duration=2., n_spikes=5, spike_frequency=100., period=100., amplitude=1000., n=5, start=50.)
    plt.plot(p['amplitude_times'], p['amplitude_values'], '.-')
    plt.title("bursts")
    
    plt.figure()
    p = create_burst_gen_dict(duration=2., n_spikes=5, spike_frequency=100., period=100., amplitude=1000., n=2, start=50.,
                         start_spike_amplitude=2000.)
    plt.plot(p['amplitude_times'], p['amplitude_values'], '.-')
    plt.title("bursts, with singular initial spike")

    plt.show()