In [1]:
import pickle
with open("vonMisesData_100neurons.p", "rb") as input_file:
[NumNeurons, NeuronParameters, WorldParameters, Neurons,
NumTrajectories, TrajStartPos, RatRadialSpeed, TrajLength, SpikeRasters] = pickle.load(input_file)
In [2]:
# All imports here...
import numpy as np
import time
from hmmlearn import hmm # see https://github.com/ckemere/hmmlearn
import seaborn as sns
from matplotlib import pyplot as plt
%matplotlib inline
# display place field coverage of a particular environment
sns.set(rc={'figure.figsize': (18, 4),'lines.linewidth': 2, 'font.size': 18, 'axes.labelsize': 16, 'legend.fontsize': 12, 'ytick.labelsize': 12, 'xtick.labelsize': 12 })
sns.set_style("white")
In [3]:
def BinSpikeRasters(Rasters, BinWidth=0.25, NBins=0) :
# Rasters is a list of ndarrays, where each array contains spike times for a neuron
if (NBins == 0) :
b = 0.0;
for spk_ts in Rasters :
if (len(spk_ts) > 0) :
b = max(b, (spk_ts[-1] / BinWidth))
NBins = np.int(np.ceil(b))
BinnedRasters = np.zeros((NBins, len(Rasters)))
for k, spk_ts in enumerate(Rasters) :
for s in spk_ts :
BinnedRasters[np.int(s/BinWidth), k] += 1
return BinnedRasters
In [4]:
t0 = time.time();
# Train model with first environment
NTrain = 90
NTest = 10
BinWidth = 0.25 # 250 ms bins
NBins = np.int(TrajLength / BinWidth)
TrainingData = []
for w in range(WorldParameters['NEnv']) :
TrainingData.append([])
for k in range(NTrain) :
TrainingData[w].append(BinSpikeRasters(SpikeRasters[w][k], BinWidth=BinWidth, NBins=NBins))
t1 = time.time();
print("Time elapsed for binning: ", t1-t0)
In [5]:
[r,c] = TrainingData[w][0].shape
StackedTrainingData = np.array((r,c))
TrainingSequenceLengths = []
for idx in range(len(TrainingData[0])) :
#l = np.random.random_integers(r/2,r)
l = r
TrainingSequenceLengths.append(l)
if (idx == 0) :
StackedTrainingData = TrainingData[0][idx][0:l,:]
else :
StackedTrainingData = np.vstack((StackedTrainingData,TrainingData[0][idx][0:l,:]))
In [14]:
# Compare different numbers of states
DifferentStateNumberModels = []
NStates = [8,16,24,32,64]
t0 = time.time();
for n in NStates :
model = hmm.PoissonHMM(n_components=n, n_iter=100, tol=1e-4, init_params='smt')
DifferentStateNumberModels.append(model)
for idx in range(len(NStates)) :
t1 = time.time();
# Build an HMM instance and set parameters
DifferentStateNumberModels[idx].fit(StackedTrainingData, lengths=TrainingSequenceLengths)
t2 = time.time();
print(t2-t1)
t3 = time.time();
print(t3-t0) # ~120 s total
In [9]:
def ArrangeTransitionMatrix(tmat, means) :
[NStates, _] = tmat.shape
new_order = [0]
rem_states = np.arange(1,NStates).tolist()
cs = 0
for ii in np.arange(0,NStates-1):
nstilde = np.argmax(tmat[cs,rem_states])
ns = rem_states[nstilde]
rem_states.remove(ns)
cs = ns
new_order.append(cs)
tmatnew = tmat[:, new_order][new_order]
meanmat = means[new_order,:]
return [tmatnew, meanmat]
In [10]:
[newtmat, newmeans] = ArrangeTransitionMatrix(DifferentStateNumberModels[0].transmat_, DifferentStateNumberModels[0].means_)
In [15]:
from hinton import hinton
f, axarr = plt.subplots(1,len(NStates))
for idx in range(len(NStates)) :
plt.sca(axarr[idx])
[newtmat, newmeans] = ArrangeTransitionMatrix(DifferentStateNumberModels[idx].transmat_, DifferentStateNumberModels[idx].means_)
hinton(newtmat.T)
In [ ]:
DifferentStateNumberSequenceLL = []
t1 = time.time();
for idx in range(len(NStates)) :
DifferentStateNumberSequenceLL.append(np.zeros(NTest))
for idx in range(len(NStates)) :
for i in range(NTest) :
DifferentStateNumberSequenceLL[idx][i] = DifferentStateNumberModels[idx].score(BinSpikeRasters(SpikeRasters[0][NTrain + i]))
t2 = time.time();
print(t2-t1)
meanLL = []
for ll in DifferentStateNumberSequenceLL:
meanLL.append(np.mean(ll))
print(meanLL)