Multidimensional Array deleting entire max record keeping information across in order

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IDN
IDN on 22 Dec 2021
Commented: IDN on 25 Dec 2021
I have the following loop:
sz = 20;
m = zeros(size(sz));
for i = 1:sz
[max_val, position] = max(sh(:)); %Find Max Position
m(i,:) = [position]; %Store Max Position in "m"
sh(sh==max(sh)) = []; %Delete current max value of "sh"
end
What I am trying to do here is pretty much to extract to "m" the top 20 highest values in "sh" (sh is a 3D matrix - 100x60x95). What i am not sure is happening is if " sh(sh==max(sh)) = []; " deletes only the value or the entire "row" containig the data of the max value.
What i ultimately need is once i delete the value, i need to delete everything else pertaining to that value in the matrix so when values shift they keep their order. Thanks so much for the help!
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Accepted Answer

Voss
Voss on 23 Dec 2021
If all you need is the 20 maximum values and their positions (either linear index or subscript index), then you can do this:
sh_temp = sh;
sh_temp(isnan(sh_temp)) = -Inf;
[sh_sort,ii] = sort(sh_temp(:),'descend');
sz = 20;
max_vals = sh_sort(1:sz);
m = ii(1:sz); % linear index of max_vals
[r,c,p] = ind2sub(size(sh),m); % row, column, 'page' index for each of max_vals
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