[PLUG] Python Lists and File Reads

[Rich Shepard]

On Fri, 15 Jul 2005, Shahms King wrote:

> I think you probably want to get rid of the quotes around both  of those
> ~ arguments.  Additionally, what's the point of passing "input" and
> "output" as parameters if you never actually use the values?

Shahms,

   I tried using input, but it was an empty string. After I assigned it I
could see the contents.

   I've four books on python (two ORA books by Mark Lutz and a couple
downloaded from the web), but I cannot find answers to questions such as I've
posted here. I wanted to use input as a list, not just a file handle, but
that wasn't working for me.

> | src = input.read()
>
> This will read the entire input into a single string.
> You probably meant to say:
>
> src = input.read().split()

   Thank you.

> Additionally, (assuming I read your intention correctly) your loop
> probably makes more sense as:
>
> ----------------------------------
> for i,elem1 in enumerate(src):
> ~  for j,elem2 in enumerate(src):
> ~   if i < j:
> ~     print >>output, (elem1,elem2)
> ----------------------------------
>
> Or, alteratively:
>
> ----------------------------------
> for i,elem1 in enumerate(src):
> ~  for elem2 in src[i+1:]:
> ~    print >>output, (elem1, elem2)
> -----------------------------------

   The loop worked fine when I was working with a list. I've no idea if I
want a list or a split string. My references did not give me any insight into
this.

Many thanks,

Rich

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