extracting numbers from a file, excluding words

[Kristina Kudriašova]

1 Nov 2005 09:19:45 -0800, dawenliu at gmail.com <dawenliu at gmail.com>:
> Hi, I have a file with this content:
>
> zzzz zzzzz zzz zzzzz
> ...
> xxxxxxx xxxxxxxxxx xxxxx 34.215
> zzzzzzz zz zzzz
> ...
>

Hi,

I'd suggest doing this:

f = file('...')
for line in f:
    if 'xxxxxxx xxxxxxxxxx xxxxx' in line:
        var = float(line[len('xxxxxxx xxxxxxxxxx xxxxx'):].strip())
f.close()