On 2013-04-22, Oscar Benjamin <oscar.j.benja...@gmail.com> wrote:
> On 22 April 2013 15:24, Neil Cerutti <ne...@norwich.edu> wrote:
>>
>> Hrmmm, hoomm. Nobody cares for slicing any more.
>>
>> def headered_groups(lst, header):
>> b = lst.index(header) + 1
>> while True:
>> try:
>> e = lst.index(header, b)
>> except ValueError:
>> yield lst[b:]
>> break
>> yield lst[b:e]
>> b = e+1
>
> This requires the whole file to be read into memory. Iterators
> are typically preferred over list slicing for sequential text
> file access since you can avoid loading the whole file at once.
> This means that you can process a large file while only using a
> constant amount of memory.
I agree, but this application processes unknowns-sized slices,
you have to build lists anyhow. I find slicing much more
convenient than accumulating in this case, but it's possibly a
tradeoff.
> with open('data.txt') as inputfile:
> for group in headered_groups(map(str.strip, inputfile)):
> print(group)
Thanks, that's a nice improvement.
--
Neil Cerutti
--
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