[Numpy-discussion] recarray slow?

wheres pythonmonks wherespythonmonks at gmail.com
Wed Jul 21 16:35:21 EDT 2010


What about:

idx_by_name = dict(enumerate(d.dtype.names))

Then I can look up the index of the columns I want before the loop,
and then access by the index during the loop.

- W



On Wed, Jul 21, 2010 at 4:29 PM, Pierre GM <pgmdevlist at gmail.com> wrote:
>
> On Jul 21, 2010, at 4:22 PM, wheres pythonmonks wrote:
>
>> However: is there an automatic way to convert a named index to a position?
>>
>> What about looping over tuples of my recarray:
>>
>> for t in d:
>>    date = t['Date']
>>    ....
>
> Why don't you use zip ?
>
>>>> for (date, t) in (d['Date'], d)
>
> That way, you save repetitive calls to __getitem__....
>
>> Should I create a map from dtype.names(), and use that to look up the
>> index based on the name in advance?  (if I really really want to
>> factorize out the lookup of 'Date']
>
>
> Meh. I have a bad feeling about it that it won't be really performant.
>
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