On 17 dec, 12:20, "Günther Dietrich" <gd.use...@spamfence.net> wrote: > nukeymusic <nukeymu...@gmail.com> wrote: > >I'm trying to calculate the difference in seconds between two > > [...] > > >>> import datetime > >>> date1 = datetime.datetime.strptime("Dec-13-09:47:12", "%b-%d-%H:%M:%S") > >>> date2 = datetime.datetime.strptime("Dec-13-09:47:39", "%b-%d-%H:%M:%S") > >>> delta = date2 - date1 > >>> delta_seconds = (delta.days * 60 * 60 * 24) + delta.seconds + > >>> ((delta.microseconds + 500000) / 1000000) > > For very big time differences you should consider to use the Decimal > arithmetics (standard module Decimal) instead of integer arithmetics > for the last line. > If you are sure, that you don't use fractional seconds, you can omit > the part with 'delta.microseconds'. > > Best regards, > > Günther That can very much Günther, this helped me a lot further, I'm only struggling with one more problem to finish my first python-program. Could you tell me why I can't write to the outputfile as I do in the code below:? #!/usr/bin/python #version 16/12/2011 #Example of testfile #Dec-13-09:46:45 21.4 +4.76442190E-01 8.135530E-06 1.553691E+00 #Dec-13-09:47:12 21.4 +4.76439120E-01 8.135839E-06 1.553726E+00 #Dec-13-09:47:39 21.4 +4.76427260E-01 8.136261E-06 1.553853E+00 import datetime f = open('testfile','r') g = open('outputfile','w') #get line 1 from input file: line1=f.readline() #get first element in line 1: date1=line1.rsplit()[0] #convert first element tot structured date time struct_date1=datetime.datetime.strptime(date1, "%b-%d-%H:%M:%S") for line in f: temp=line.rsplit() delta=datetime.datetime.strptime(temp[0], "%b-%d-%H:%M:%S")- datetime.datetime.strptime(date1, "%b-%d-%H:%M:%S") delta_seconds = (delta.days * 60 * 60 * 24) + delta.seconds + ((delta.microseconds + 500000) / 1000000) temp[0]=delta_seconds #the following line is wrong, but I don't know how to fix it: g.write(temp) #Close files f.close() g.close()
thanks in advance nukey -- http://mail.python.org/mailman/listinfo/python-list