Mercurial > hg > nsaunier > traffic-intelligence

comparison trafficintelligence/utils.py @ 1103:7594802f281a

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added constant distribution
author Nicolas Saunier <nicolas.saunier@polymtl.ca>
date Fri, 01 Mar 2019 13:17:44 -0500
parents 10205bd0e0b7
children e62c2f5e25e6
comparison
equal deleted inserted replaced
1102:cdf1773ba89e 1103:7594802f281a
134 134
135 def computeChi2(expected, observed): 135 def computeChi2(expected, observed):
136 '''Returns the Chi2 statistics''' 136 '''Returns the Chi2 statistics'''
137 return sum([((e-o)*(e-o))/float(e) for e, o in zip(expected, observed)]) 137 return sum([((e-o)*(e-o))/float(e) for e, o in zip(expected, observed)])
138 138
139 class ConstantDistribution(object):
140 '''Distribution returning always the same value for the random variable '''
141 def __init__(self, value):
142 self.value = value
143
144 def rvs(self, size = 1):
145 if size == 1:
146 return self.value
147 else:
148 return array([self.value]*size)
149
139 class EmpiricalContinuousDistribution(rv_continuous): 150 class EmpiricalContinuousDistribution(rv_continuous):
140 def __init__(self, values, probabilities, **kwargs): 151 def __init__(self, values, probabilities, **kwargs):
141 '''The values (and corresponding probabilities) are supposed to be sorted by value 152 '''The values (and corresponding probabilities) are supposed to be sorted by value
142 for v, p in zip(values, probabilities): P(X<=v)=p''' 153 for v, p in zip(values, probabilities): P(X<=v)=p'''
143 assert probabilities[0]==0 154 assert probabilities[0]==0