How to find the min(max) value and its index in a multidimensional matrix?

The problem is that the min(array(:)) returns the index of the min(max) as a number, while I am searching for the indices of it.

Answer 1

[Konstantinos Fragkakis]

Function to calculate the minimum value and its indices, in a multidimensional array -  In order to find the max, just replace the min(array(:)) statement with max(array(:)).

    function [ minimum,index ] = minmat( array )
       % Function: Calculate the minimum value and its indices in a multidimensional array

     % -------- Logic description --------
     % First of all, identify the Matlab convention for numbering the elements of a multi-dimensional array.
     %   First are all the elements for the first dimension
     %   Then the ones for the second and so on
     % In each iteration, divide the number that identifies the minimum with the dimension under investigation
     %   The remainder is the Index for this dimension (check for special cases below)
     %   The integer is the "New number" that identifies the minimum, to be used for the next loop
     % Repeat the steps as many times as the number of dimensions (e.g for a 2-by-3-by-4-by-5 table, repeat 4 times)

        neldim      = size(array);              % Length of each dimension
        ndim        = length(neldim);           % Number of dimensions
        [minimum,I] = min(array(:));        

        remaining = 1;                          % Counter to evaluate the end of dimensions
        index = [];                             % Initialize index

        while remaining~=ndim+1                 % Break after the loop for the last dimension has been evaluated

           % Divide the integer with the the value of each dimension --> Identify at which group the integer belongs    
           r       = rem(I,neldim(remaining)); % The remainder identifies the index for the dimension under evaluation
           int     = fix(I/neldim(remaining)); % The integer is the number that has to be used for the next iteration
           if r == 0                           % Compensate for being the last element of a "group" --> It index is equal to the dimension under evaluation
               new_index   = neldim(remaining);
           else                                % Compensate for the number of group --> Increase by 1 (e.g if remainder 8/3 = 2 and integer = 2, it means that you are at the 2+1 group in the 2nd position)
               int         = int+1;
               new_index   = r;                    
           end
           I     = int;                        % Adjust the new number for the division. This is the group th
           index = [index new_index];          % Append the current index at the end       
           remaining = remaining + 1;
        end
    end