[Tutor] newbie question about list element manipulation after split()

[Emad Nawfal (عماد نوفل)]

On Thu, Oct 16, 2008 at 4:25 AM, Visvaldas K. <coyote_v2002 at yahoo.com>wrote:

> Hi,
>
> I feel very stupid, but I am stuck. I could try some workaround, but I want
> to understand what I am doing wrong.
>
> The line:
>
> for line in open("parameterfile").readlines( ):
>    print line.split()                # trouble line
>
>
> The "trouble line" works fine in this example. It prints
> what I want, something which looks like lists of words:
>
> ['CT', 'CT', '268.0', '1.529']...  etc.
>
> However, if I want to manipulate the individual list elements, I run into
> trouble. While
>
> print line.split()[0]
>
> still works, (it yields CT  - first element),
>
> however,
>
> print line.split()[1]
>
> gives error:
>
> File "readatoms.py", line 103, in <module>
>    print line.split()[1]
> IndexError: list index out of range
>
> Could you please tell me what's wrong. (I come from Perl background so
> Python seems out-of-the-body experience to me).
>
> Sincerely,
>
> Vis
>

Here is a solution:
>>> for line in open('DBAN1001.txt').readlines():
...     line = line.split()
...     if len(line) > 1: # This is what makes it work for me.
...             print line[1]
...
it's
have
the
way
that
is
is
prison
we


It works fine. It seems that in the file you have there are lines whose
length is less than you should expect, or maybe a more experienced Python
programmer can give you a better answer.


>
>
>
>
>
>
>
>
>
>
>
>
>
> _______________________________________________
> Tutor maillist  -  Tutor at python.org
> http://mail.python.org/mailman/listinfo/tutor
>



-- 
لا أعرف مظلوما تواطأ الناس علي هضمه ولا زهدوا في إنصافه كالحقيقة.....محمد
الغزالي
"No victim has ever been more repressed and alienated than the truth"

Emad Soliman Nawfal
Indiana University, Bloomington
http://emnawfal.googlepages.com
--------------------------------------------------------
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/tutor/attachments/20081016/4eab3100/attachment.htm>