[Numpy-discussion] Is there a pure numpy recipe for this?

[Chris Barker]

On Wed, Mar 26, 2014 at 2:23 PM, Slaunger <Slaunger at gmail.com> wrote:

> Only I did not know about the append and insert methods. Very, very nice!
> (I
> only knew concatenate, which would be clumsy for just appending one
> element),
>
Sorry -- I dont have the time to actually figure out what you are doing,
but:::

note that  numpy arrays are not re-sizable, so np.append() and np.insert()
have to make a new array, and copy all the old data over. If you are
appending one at a time, this can be pretty darn slow.

I wrote a "grow_array" class once, it was a wrapper around a numpy array
that pre-allocated extra data to make appending more efficient. It's kind
of half-baked code now, but let me know if you are interested.

-Chris





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