[Numpy-discussion] numpy.append & numpy.where vs list.append and brute iterative for loop

[Christopher Barker]

On 1/27/11 1:53 PM, Sturla Molden wrote:
> But N appends are O(N) for lists and O(N*N) for arrays.

hmmm - that doesn't seem quite right -- lists still have to re-allocate 
and copy, they just do it every n times (where n grows with the list), 
so I wouldn't expect exactly O(N).

But you never know 'till you profile. See the enclosed code and figures.

Interestingly both appear to be pretty linear, though the constant is 
Much larger for numpy arrays.

-Chris









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