MATLAB: Nested For Loop for 2D Matrix

nested for loops

I want to create a nested for loop that essentially goes through a 2D matrix of 600×1000 dimensions, such that in every loop in both of the dimensions it picks out exactly 51×51 part of the 2D matrix in either of the dimensions and multiplies it to another 51×51 separate matrix.

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So then you want to extract random 51x51 submatrices? If so, then,

I=sort(randperm(600,51));
J=sort(randperm(1000,51));
submatrix= matrix(I,J);

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MATLAB: I worked on nested loop.

Assuming that your goal is to understand loops, try this

>> [ a01, a02 ] = cssm();
>> all(a01(:)==a02(:))
ans =
     1

where

function  [ a01, a02 ] = cssm()
    y   = randi( 100, [3,24] );
    a01 = nan([46,24]);
    a02 = nan([46,24]);
    kk  = 1;
    while kk<3
        sub = y(kk,:);
        kk  = kk+1;
        jj  = 1;
        while jj<24
            a01((kk-2)*23+jj,:)=sub;
            jj = jj+1;
        end
    end
    for kk = 1 : 2
        for jj = 1 : 23
            a02((kk-1)*23+jj,:) = y(kk,:);
        end
    end
end

&nbsp

Comment: &nbsp The codes based on while-loops and for-loops, respectively, produces identical answers. In this special case for-loops are easier to work with than while-loops.

"but i get a 23 by 24 matrix". That's because in the second turn of the outer loop the counter, j, has the value 24 and the code of the inner loop will not execute.

Stalin's answer provides a more efficient solution, which takes advantage of special features of Matlab.

MATLAB: Multiple loop do not loop

for i=1:noofcol
    for j=1:noofrow

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MATLAB: I worked on nested loop.

MATLAB: Multiple loop do not loop

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