# How to calculate maximum up to current point?

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Steven Niggebrugge on 18 Aug 2017
Commented: John D'Errico on 18 Aug 2017
Hi, how can i calculate the an array of current maxima, i.e. for each point in the array to calculate the maximum from the first observation of the array to the current? e.g. for array [3 8 10 6] i want the output to be [3 8 10 6] ?
Is there a function to do this (movmax i think it works for a fixed lookback or lookforward) or do i just need to loop through all observations?
José-Luis on 18 Aug 2017
You probably meant [3,8,10,10] as your result.
Steven Niggebrugge on 18 Aug 2017
yes indeed, thanks very much!

John D'Errico on 18 Aug 2017
cummax([3 8 10 6])
ans =
3 8 10 10
José-Luis on 18 Aug 2017
Edited: José-Luis on 18 Aug 2017
+1
Whenever I think of a tortured way, there's a built-in function. It is hard to keep up.
John D'Errico on 18 Aug 2017
I keep learning new things on Answers. New little goodies that appeared when I was not watching. I guess we all should read the release notes religiously. That would take all the fun out of it though. :)

José-Luis on 18 Aug 2017
a = [3,8,10,6,5,11,12,-20];
n = numel(a);
result = tril(bsxfun(@minus,a,a'));
[~,idx] = max(result,[],2);
result = a(idx)