jidt/tester.py

114 lines
4.2 KiB
Python
Executable File

##
## Java Information Dynamics Toolkit (JIDT)
## Copyright (C) 2012, Joseph T. Lizier
##
## This program is free software: you can redistribute it and/or modify
## it under the terms of the GNU General Public License as published by
## the Free Software Foundation, either version 3 of the License, or
## (at your option) any later version.
##
## This program is distributed in the hope that it will be useful,
## but WITHOUT ANY WARRANTY; without even the implied warranty of
## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
## GNU General Public License for more details.
##
## You should have received a copy of the GNU General Public License
## along with this program. If not, see <http://www.gnu.org/licenses/>.
##
# = Example 4 - Transfer entropy on continuous data using Kraskov estimators =
# Simple transfer entropy (TE) calculation on continuous-valued data using the Kraskov-estimator TE calculator.
from jpype import *
import random
import math
import os
import numpy as np
NUM_REPS = 10
NUM_SPIKES = int(1e4)
# Params for canonical example generation
RATE_Y = 1.0
RATE_X_MAX = 10
def generate_canonical_example_processes(num_y_events):
event_train_x = []
event_train_x.append(0)
event_train_y = np.random.uniform(0, int(num_y_events / RATE_Y), int(num_y_events))
event_train_y.sort()
most_recent_y_index = 0
previous_x_candidate = 0
while most_recent_y_index < (len(event_train_y) - 1):
this_x_candidate = previous_x_candidate + random.expovariate(RATE_X_MAX)
while most_recent_y_index < (len(event_train_y) - 1) and this_x_candidate > event_train_y[most_recent_y_index + 1]:
most_recent_y_index += 1
delta_t = this_x_candidate - event_train_y[most_recent_y_index]
rate = 0
if delta_t > 1:
rate = 0.5
else:
rate = 0.5 + 5.0 * math.exp(-50 * (delta_t - 0.5)**2) - 5.0 * math.exp(-50 * (0.5)**2)
if random.random() < rate/float(RATE_X_MAX):
event_train_x.append(this_x_candidate)
previous_x_candidate = this_x_candidate
event_train_x.sort()
event_train_y.sort()
return event_train_x, event_train_y
# Change location of jar to match yours (we assume script is called from demos/python):
jarLocation = os.path.join(os.getcwd(), "infodynamics.jar");
if (not(os.path.isfile(jarLocation))):
exit("infodynamics.jar not found (expected at " + os.path.abspath(jarLocation) + ") - are you running from demos/python?")
# Start the JVM (add the "-Xmx" option with say 1024M if you get crashes due to not enough memory space)
startJVM(getDefaultJVMPath(), "-ea", "-Djava.class.path=" + jarLocation)
teCalcClass = JPackage("infodynamics.measures.spiking.integration").TransferEntropyCalculatorSpikingIntegration
teCalc = teCalcClass()
teCalc.setProperty("knns", "4")
print("Independent Poisson Processes")
teCalc.setProperty("k_HISTORY", "1")
teCalc.setProperty("l_HISTORY", "1")
results_poisson = np.zeros(NUM_REPS)
for i in range(NUM_REPS):
sourceArray = NUM_SPIKES*np.random.random(NUM_SPIKES)
sourceArray.sort()
destArray = NUM_SPIKES*np.random.random(NUM_SPIKES)
destArray.sort()
teCalc.setObservations(JArray(JDouble, 1)(sourceArray), JArray(JDouble, 1)(destArray))
result = teCalc.computeAverageLocalOfObservations()
print("TE result %.4f nats" % (result,))
results_poisson[i] = result
print("Summary: mean ", np.mean(results_poisson), " std dev ", np.std(results_poisson))
print("Canonical example")
teCalc.setProperty("k_HISTORY", "2")
teCalc.setProperty("l_HISTORY", "1")
results_canonical = np.zeros(NUM_REPS)
for i in range(NUM_REPS):
event_train_x, event_train_y = generate_canonical_example_processes(NUM_SPIKES)
teCalc.setObservations(JArray(JDouble, 1)(event_train_y), JArray(JDouble, 1)(event_train_x))
result = teCalc.computeAverageLocalOfObservations()
results_canonical[i] = result
print("TE result %.4f nats" % (result,))
print("Summary: mean ", np.mean(results_canonical), " std dev ", np.std(results_canonical))