Question

Completely new to python i’m having problems finding this with version 2.4

I have a text file that contains 3 columns they are tab delimited by not a single tab, 9 tabs.
1000 line file
ex:

$1$sda4356:[sgb1_diska5.ldlbat44.libabl]talild_0329_base.rpt                                talild_0329_base.rpt                                                                      00000000000000005062

What i need to do is sort everything by column 3 ( 00000000000000005062 ).

Is using the csv reader the best way to handle doing this? how do i get it to handle the fact that my text file is using 9 tabs to seperate each column. Most other things i’m finding are incompatiable with python 2.4.

Answer 1

Since you’re using 9 tabs, str.split seems like it should be able to handle this properly, (but I don’t see any reason why csv would choke on it …):

fobj = open('data.csv')
data = [ x.split() for x in fobj ]
fobj.close()  #don't forget to close :)

Or possibly:

delim = '\t'*9
data = [ x.split(delim) for x in fobj ]

Then you can sort that. In a newer version of python, you’d do:

from operator import itemgetter
data.sort(key=itemgetter(2))

Try this first! (According to the comments and the documentation, key is supported in python2.4, but not python2.3). operator.itemgetter is also “new in python2.4” and itemgetter(2) is equivalent to lambda x:x[2] or the more verbose:

def get2(x):
    return x[2]

---

But I think you might need to rely on cmp for compatability with really old python versions (Note, that python3 no longer supports cmp):

def compare(x1,x2):
    if x1[2] > x2[2]:
       return 1
    elif x1[2] < x2[2]:
       return -1
    else:
       return 0

and then you’d sort:

data.sort(cmp=compare)