loops - MATLAB: Faster pre-allocation of zeros-matrix -

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this question has answer here:

/edit: see here interesting discussion of topic. @dan

using a(m,n) = 0 appears faster, depending of size of matrix a, a = zeros(m,n). both variants same when comes pre-allocation before loop?

they definately not same.

though there ways beat performance of a=zeros(m,n), doing a(m,n) = 0 not safe way it. if entries in a exist keep existing.

see this nice options, consider doing loop backwards if don't mind risk.


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