Return the indices of max value in a possible 4D array

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I'm trying to get the indices of a max value from a 4 dimension array, that can actually reduce in dimension, so I can display this value and some the value of some other variables at one or more of the same indices. I used something like this:
MAX = find(sx == max(sx(:)));
if MAX/(kk*qq*zz) > 1
rmax = floor(MAX/(kk*qq*zz)) + 1;
MAX = MAX - (kk*qq*zz) * (rmax - 1);
else
if length(theta) == 1
rmax = 0;
rmax = 1;
end
if MAX/(kk*qq) > 1
zmax = floor(MAX/(kk*qq)) + 1;
MAX = MAX - (kk*qq) * (zmax - 1);
else
zmax = 1;
end
if MAX/kk > 1
qmax = floor(MAX/kk) + 1;
MAX = MAX - (kk) * (qmax - 1);
else
qmax = 1;
end
kmax = MAX;
smax = sx(kmax, qmax, zmax, rmax);
but if the array size changes it still wants to output smax as a 4 dimensional array except its not so I get an error.
Is there any function in Matlab for getting these indices?

Accepted Answer

Andrew Newell
Andrew Newell on 20 Feb 2015
Edited: Andrew Newell on 20 Feb 2015
If you don't know in advance the size of the array, you can create a cell array for the indices with as many elements as there are dimensions:
[MAX,I] = max(sx(:));
dims = size(sx);
smax = cell(size(dims));
[smax{:}] = ind2sub(dims,I);
  3 Comments
Andrew Newell
Andrew Newell on 20 Feb 2015
That would be more transparent. My code is rather cryptic.
Samuel Mustapha
Samuel Mustapha on 20 Feb 2015
Thank you so much. Ind2sub worked on its own. It's a varargout function and it has an if statement for putting ones in empty dimensions. Since I know the max dimension I'll have, it worked. Thanks again.

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