## How to calculate maximum up to current point?

### Steven Niggebrugge (view profile)

on 18 Aug 2017
Latest activity Commented on by John D'Errico

### John D'Errico (view profile)

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

### José-Luis (view profile)

on 18 Aug 2017
You probably meant [3,8,10,10] as your result.
Steven Niggebrugge

### Steven Niggebrugge (view profile)

on 18 Aug 2017
yes indeed, thanks very much!

### John D'Errico (view profile)

on 18 Aug 2017

cummax([3 8 10 6])
ans =
3 8 10 10

José-Luis

### José-Luis (view profile)

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

### John D'Errico (view profile)

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 (view profile)

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)