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comparison python/storage.py @ 744:ed6ff2ec0aeb dev

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bug correction from Laurent Gauthier
author Nicolas Saunier <nicolas.saunier@polymtl.ca>
date Thu, 10 Sep 2015 15:48:01 -0400
parents 867bab9f317a
children 6049e9b6902c
comparison
equal deleted inserted replaced
741:5b91b8d97cf3 744:ed6ff2ec0aeb
827 if npsum(diff == 0.) >= proportionStationaryTime*len(positions): 827 if npsum(diff == 0.) >= proportionStationaryTime*len(positions):
828 nStationary += 1 828 nStationary += 1
829 829
830 return nStationary, nVehicles 830 return nStationary, nVehicles
831 831
832 def countCollisionsVissim(filename, lanes = None, collisionTimeDifference = 0.2): 832 def countCollisionsVissim(filename, lanes = None, collisionTimeDifference = 0.2, lowMemory = True):
833 '''Counts the number of collisions per lane in a VISSIM trajectory file 833 '''Counts the number of collisions per lane in a VISSIM trajectory file
834 834
835 To distinguish between cars passing and collision, 835 To distinguish between cars passing and collision,
836 one checks when the sign of the position difference inverts 836 one checks when the sign of the position difference inverts
837 (if the time are closer than collisionTimeDifference) 837 (if the time are closer than collisionTimeDifference)
838 If lanes is not None, only the data for the selected lanes will be provided 838 If lanes is not None, only the data for the selected lanes will be provided
839 (format as string x_y where x is link index and y is lane index)''' 839 (format as string x_y where x is link index and y is lane index)'''
840 from pandas import read_csv, merge 840 from pandas import read_csv, merge
841 data = read_csv(filename, delimiter=';', comment='*', header=0, skiprows = 1, usecols = ['LANE\LINK\NO', 'LANE\INDEX', '$VEHICLE:SIMSEC', 'NO', 'POS'], low_memory = lowMemory) 841 data = read_csv(filename, delimiter=';', comment='*', header=0, skiprows = 1, usecols = ['LANE\LINK\NO', 'LANE\INDEX', '$VEHICLE:SIMSEC', 'NO', 'POS'], low_memory = lowMemory)
842 data = selectPDLanes(data, lanes) 842 data = selectPDLanes(data, lanes)
843 data = data.convert_objects(convert_numeric=True)
844
843 merged = merge(data, data, how='inner', left_on=['LANE\LINK\NO', 'LANE\INDEX', '$VEHICLE:SIMSEC'], right_on=['LANE\LINK\NO', 'LANE\INDEX', '$VEHICLE:SIMSEC'], sort = False) 845 merged = merge(data, data, how='inner', left_on=['LANE\LINK\NO', 'LANE\INDEX', '$VEHICLE:SIMSEC'], right_on=['LANE\LINK\NO', 'LANE\INDEX', '$VEHICLE:SIMSEC'], sort = False)
844 merged = merged[merged['NO_x']>merged['NO_y']] 846 merged = merged[merged['NO_x']>merged['NO_y']]
845 847
846 nCollisions = 0 848 nCollisions = 0
847 for name, group in merged.groupby(['LANE\LINK\NO', 'LANE\INDEX', 'NO_x', 'NO_y']): 849 for name, group in merged.groupby(['LANE\LINK\NO', 'LANE\INDEX', 'NO_x', 'NO_y']):
848 diff = group['POS_x'].convert_objects(convert_numeric=True)-group['POS_y'].convert_objects(convert_numeric=True) 850 diff = group['POS_x']-group['POS_y']
849 # diff = group['POS_x']-group['POS_y'] # to check the impact of convert_objects and the possibility of using type conversion in read_csv or function to convert strings if any 851 # diff = group['POS_x']-group['POS_y'] # to check the impact of convert_objects and the possibility of using type conversion in read_csv or function to convert strings if any
850 if len(diff) >= 2 and npmin(diff) < 0 and npmax(diff) > 0: 852 if len(diff) >= 2 and npmin(diff) < 0 and npmax(diff) > 0:
851 xidx = diff[diff < 0].argmax() 853 xidx = diff[diff < 0].argmax()
852 yidx = diff[diff > 0].argmin() 854 yidx = diff[diff > 0].argmin()
853 if abs(group.loc[xidx, '$VEHICLE:SIMSEC'] - group.loc[yidx, '$VEHICLE:SIMSEC']) <= collisionTimeDifference: 855 if abs(group.loc[xidx, '$VEHICLE:SIMSEC'] - group.loc[yidx, '$VEHICLE:SIMSEC']) <= collisionTimeDifference: