Lee Chaplin wrote: > Hi all, > > I am trying to sort, in place, by column, a csv file AND sort it case > insensitive. > I was trying something like this, with no success: > > import csv > import operator > > def sortcsvbyfield(csvfilename, columnnumber): > with open(csvfilename, 'rb') as f: > readit = csv.reader(f) > thedata = list(readit) > > thedata = sorted(thedata, key = lambda x: > (operator.itemgetter(columnnumber) ,x[0].lower())) #!!! > with open(csvfilename, 'wb') as f: > writeit = csv.writer(f) > writeit.writerows(thedata) > > The line marked is the culprit. > Any help is greatly appreciated.
Try out your sort key on interactively: >>> import csv >>> import operator >>> columnnumber = 0 >>> sortkey = lambda x: (operator.itemgetter(columnnumber), x[0].lower()) >>> sortkey(["an", "example", "row"]) (<operator.itemgetter object at 0x7feda34fdc90>, 'an') >>> sortkey(["an", "example", "row"]) (<operator.itemgetter object at 0x7feda350b690>, 'an') >>> sortkey(["an", "example", "row"]) (<operator.itemgetter object at 0x7feda34fdc90>, 'an') Effectively you are sorting your data by the id (memory address) of the itemgetters you create. You probably want >>> def sortkey(row): ... column = row[columnnumber] ... return column.lower(), column ... >>> sorted([[col] for col in "alpha ALPHA beta GAMMA gamma".split()], key=sortkey) [['ALPHA'], ['alpha'], ['beta'], ['GAMMA'], ['gamma']] Alternatively you can use >>> import locale >>> locale.setlocale(locale.LC_ALL, "") 'de_DE.UTF-8' >>> sorted([[col] for col in "alpha ALPHA beta GAMMA gamma".split()], key=lambda row: locale.strxfrm(row[columnnumber])) [['alpha'], ['ALPHA'], ['beta'], ['gamma'], ['GAMMA']] -- http://mail.python.org/mailman/listinfo/python-list
