changeset 687:de278c5e65f6 dev

minor comments for lognormal parameters (numpy and usual names differ)
author Nicolas Saunier <nicolas.saunier@polymtl.ca>
date Mon, 22 Jun 2015 15:27:33 +0200
parents cdee6a3a47b4
children f2b52355a286
files python/utils.py scripts/classify-objects.py
diffstat 2 files changed, 3 insertions(+), 1 deletions(-) [+]
line wrap: on
line diff
--- a/python/utils.py	Tue Jun 09 17:29:03 2015 +0200
+++ b/python/utils.py	Mon Jun 22 15:27:33 2015 +0200
@@ -27,6 +27,8 @@
 #########################
 
 def logNormalMeanVar(loc, scale):
+    '''location and scale are respectively the mean and standard deviation of the normal in the log-normal distribution
+    https://en.wikipedia.org/wiki/Log-normal_distribution'''
     mean = exp(loc+(scale**2)/2)
     var = (exp(loc**2)-1)*exp(2*loc+scale**2)
     return mean, var
--- a/scripts/classify-objects.py	Tue Jun 09 17:29:03 2015 +0200
+++ b/scripts/classify-objects.py	Mon Jun 22 15:27:33 2015 +0200
@@ -52,7 +52,7 @@
 # log logistic for ped and bik otherwise ((pedBeta/pedAlfa)*((sMean/pedAlfa)**(pedBeta-1)))/((1+(sMean/pedAlfa)**pedBeta)**2.)
 speedProbabilities = {'car': lambda s: norm(params.meanVehicleSpeed, params.stdVehicleSpeed).pdf(s),
                       'pedestrian': lambda s: norm(params.meanPedestrianSpeed, params.stdPedestrianSpeed).pdf(s), 
-                      'bicycle': lambda s: lognorm(params.scaleCyclistSpeed, loc = 0., scale = np.exp(params.locationCyclistSpeed)).pdf(s)} # lognorm shape, loc, scale
+                      'bicycle': lambda s: lognorm(params.scaleCyclistSpeed, loc = 0., scale = np.exp(params.locationCyclistSpeed)).pdf(s)} # numpy lognorm shape, loc, scale: shape for numpy is scale (std of the normal) and scale for numpy is location (mean of the normal)
 
 if args.plotSpeedDistribution:
     import matplotlib.pyplot as plt