1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245
|
""" isi_distance.py
Module containing several functions to compute the ISI profiles and distances
Copyright 2014-2015, Mario Mulansky <mario.mulansky@gmx.net>
Distributed under the BSD License
"""
from __future__ import absolute_import
import pyspike
from pyspike import PieceWiseConstFunc
from pyspike.generic import _generic_profile_multi, _generic_distance_multi, \
_generic_distance_matrix, resolve_keywords
from pyspike.isi_lengths import default_thresh
from pyspike.spikes import reconcile_spike_trains, reconcile_spike_trains_bi
############################################################
# isi_profile
############################################################
def isi_profile(*args, **kwargs):
""" Computes the isi-distance profile :math:`I(t)` of the given
spike trains. Returns the profile as a PieceWiseConstFunc object. The
ISI-values are defined positive :math:`I(t)>=0`.
Valid call structures::
isi_profile(st1, st2) # returns the bi-variate profile
isi_profile(st1, st2, st3) # multi-variate profile of 3 spike trains
spike_trains = [st1, st2, st3, st4] # list of spike trains
isi_profile(spike_trains) # profile of the list of spike trains
isi_profile(spike_trains, indices=[0, 1]) # use only the spike trains
# given by the indices
The multivariate ISI distance profile for a set of spike trains is defined
as the average ISI-profile of all pairs of spike-trains:
.. math:: <I(t)> = \\frac{2}{N(N-1)} \\sum_{<i,j>} I^{i,j},
where the sum goes over all pairs <i,j>
:returns: The isi-distance profile :math:`I(t)`
:rtype: :class:`.PieceWiseConstFunc`
"""
if len(args) == 1:
return isi_profile_multi(args[0], **kwargs)
elif len(args) == 2:
return isi_profile_bi(args[0], args[1], **kwargs)
else:
return isi_profile_multi(args, **kwargs)
############################################################
# isi_profile_bi
############################################################
def isi_profile_bi(spike_train1, spike_train2, **kwargs):
""" Specific function to compute a bivariate ISI-profile. This is a
deprecated function and should not be called directly. Use
:func:`.isi_profile` to compute ISI-profiles.
:param spike_train1: First spike train.
:type spike_train1: :class:`.SpikeTrain`
:param spike_train2: Second spike train.
:type spike_train2: :class:`.SpikeTrain`
:returns: The isi-distance profile :math:`I(t)`
:rtype: :class:`.PieceWiseConstFunc`
"""
if kwargs.get('Reconcile', True):
spike_train1, spike_train2 = reconcile_spike_trains_bi(spike_train1, spike_train2)
kwargs['Reconcile'] = False
MRTS,RI = resolve_keywords(**kwargs)
if isinstance(MRTS, str):
MRTS = default_thresh([spike_train1, spike_train2])
kwargs['MRTS'] = MRTS
# load cython implementation
try:
from .cython.cython_profiles import isi_profile_cython \
as isi_profile_impl
except ImportError:
pyspike.NoCythonWarn()
# use python backend
from .cython.python_backend import isi_distance_python \
as isi_profile_impl
times, values = isi_profile_impl(spike_train1.get_spikes_non_empty(),
spike_train2.get_spikes_non_empty(),
spike_train1.t_start, spike_train1.t_end,
MRTS)
return PieceWiseConstFunc(times, values)
############################################################
# isi_profile_multi
############################################################
def isi_profile_multi(spike_trains, indices=None, **kwargs):
""" Specific function to compute the multivariate ISI-profile for a set of
spike trains. This is a deprecated function and should not be called
directly. Use :func:`.isi_profile` to compute ISI-profiles.
:param spike_trains: list of :class:`.SpikeTrain`
:param indices: list of indices defining which spike trains to use,
if None all given spike trains are used (default=None)
:type state: list or None
:returns: The averaged isi profile :math:`<I(t)>`
:rtype: :class:`.PieceWiseConstFunc`
"""
average_dist, M = _generic_profile_multi(spike_trains, isi_profile_bi,
indices, **kwargs)
average_dist.mul_scalar(1.0/M) # normalize
return average_dist
############################################################
# isi_distance
############################################################
def isi_distance(*args, **kwargs):
""" Computes the ISI-distance :math:`D_I` of the given spike trains. The
isi-distance is the integral over the isi distance profile
:math:`I(t)`:
.. math:: D_I = \\int_{T_0}^{T_1} I(t) dt.
In the multivariate case it is the integral over the multivariate
ISI-profile, i.e. the average profile over all spike train pairs:
.. math:: D_I = \\int_0^T \\frac{2}{N(N-1)} \\sum_{<i,j>} I^{i,j},
where the sum goes over all pairs <i,j>
Valid call structures::
isi_distance(st1, st2) # returns the bi-variate distance
isi_distance(st1, st2, st3) # multi-variate distance of 3 spike trains
spike_trains = [st1, st2, st3, st4] # list of spike trains
isi_distance(spike_trains) # distance of the list of spike trains
isi_distance(spike_trains, indices=[0, 1]) # use only the spike trains
# given by the indices
:returns: The isi-distance :math:`D_I`.
:rtype: double
"""
if len(args) == 1:
return isi_distance_multi(args[0], **kwargs)
elif len(args) == 2:
return isi_distance_bi(args[0], args[1], **kwargs)
else:
return isi_distance_multi(args, **kwargs)
############################################################
# _isi_distance_bi
############################################################
def isi_distance_bi(spike_train1, spike_train2, interval=None, **kwargs):
""" Specific function to compute the bivariate ISI-distance.
This is a deprecated function and should not be called directly. Use
:func:`.isi_distance` to compute ISI-distances.
:param spike_train1: First spike train.
:type spike_train1: :class:`.SpikeTrain`
:param spike_train2: Second spike train.
:type spike_train2: :class:`.SpikeTrain`
:param interval: averaging interval given as a pair of floats (T0, T1),
if None the average over the whole function is computed.
:type interval: Pair of floats or None.
:returns: The isi-distance :math:`D_I`.
:rtype: double
"""
if kwargs.get('Reconcile', True):
spike_train1, spike_train2 = reconcile_spike_trains_bi(spike_train1, spike_train2)
kwargs['Reconcile'] = False
MRTS, RI = resolve_keywords(**kwargs)
if isinstance(MRTS, str):
MRTS = default_thresh([spike_train1, spike_train2])
kwargs['MRTS'] = MRTS
if interval is None:
# distance over the whole interval is requested: use specific function
# for optimal performance
try:
from .cython.cython_distances import isi_distance_cython \
as isi_distance_impl
return isi_distance_impl(spike_train1.get_spikes_non_empty(),
spike_train2.get_spikes_non_empty(),
spike_train1.t_start, spike_train1.t_end,
MRTS)
except ImportError:
# Cython backend not available: fall back to profile averaging
return isi_profile_bi(spike_train1, spike_train2, **kwargs).avrg(interval)
else:
# some specific interval is provided: use profile
return isi_profile_bi(spike_train1, spike_train2, **kwargs).avrg(interval)
############################################################
# isi_distance_multi
############################################################
def isi_distance_multi(spike_trains, indices=None, interval=None, **kwargs):
""" Specific function to compute the multivariate ISI-distance.
This is a deprecfated function and should not be called directly. Use
:func:`.isi_distance` to compute ISI-distances.
:param spike_trains: list of :class:`.SpikeTrain`
:param indices: list of indices defining which spike trains to use,
if None all given spike trains are used (default=None)
:param interval: averaging interval given as a pair of floats, if None
the average over the whole function is computed.
:type interval: Pair of floats or None.
:returns: The time-averaged multivariate ISI distance :math:`D_I`
:rtype: double
"""
return _generic_distance_multi(spike_trains, isi_distance_bi, indices,
interval, **kwargs)
############################################################
# isi_distance_matrix
############################################################
def isi_distance_matrix(spike_trains, indices=None, interval=None, **kwargs):
""" Computes the time averaged isi-distance of all pairs of spike-trains.
:param spike_trains: list of :class:`.SpikeTrain`
:param indices: list of indices defining which spike trains to use,
if None all given spike trains are used (default=None)
:type indices: list or None
:param interval: averaging interval given as a pair of floats, if None
the average over the whole function is computed.
:type interval: Pair of floats or None.
:returns: 2D array with the pair wise time average isi distances
:math:`D_{I}^{ij}`
:rtype: np.array
"""
return _generic_distance_matrix(spike_trains, isi_distance_bi,
indices=indices, interval=interval,
**kwargs)
|