Efficiently use length of array / vector / matrix

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Mike H
Mike H 2016-6-14
评论： Mike H 2016-6-15
I have a script that references the lengths of a few VERY long "1 by x" arrays in a few spots. Would it be more efficient to store the lengths of these arrays as variables prior to their reference?
I am currently doing lines like this:
for i = 1:1: (length(s)) % Where s is the array ....
I am not sure if Matlab forgoes recalculating the length of an array if it notices it does not change since the last time it was calculated... Thank you in advance and I apologize for my coding ignorance :)

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Walter Roberson
Walter Roberson 2016-6-14
My expectation would be that it will re-check the size of the array so it would be faster to store it. This is something you could benchmark. Note that for loops calculate the endpoints once and store the endpoints internally as constants, so any cost for doing the size() is going to be amoratized over the loop.

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