extracting numbers from a file, excluding words

[Jeffrey Schwab]

Steve Horsley wrote:
> Kristina Kudriašova wrote:
> 
>> 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()
> 
> 
> I think I prefer "if line.startswith('xxxxxxx xxxxxxxxxx xxxxx'):" . 
> Feels cleaner to me.

Especially if any "z" lines might include the magic pattern.