MATLAB: Error: subscripted assignment dimension mismatch during convolution.

convolutionerror

I am writing a code for convolution of rows of a 256×256 matrix with a column vector consisting entirely of ones. But I am getting the error "subscripted assignment dimension mismatch" every time i run the code. Any suggestions ?
for k=1:255
    for l=1:k
        m(:,l) =conv((hkl(l,:))',ones(l,1));
    end
end
'hkl' is the 256×256 matrix. I want convolve each row of hkl with a column vector of 1s whose length is equal to 'l' and store it in 'm'.

Best Answer

Not sure where you came up with that strange process. To convolve a 2D array with a column vector of l elements (which is an absolutely horrible variable name by the way), simply do this:
m = conv2(double(hkl), ones(l, 1), 'same');
In ones(), the first element is lower case L and the second argument is "one" in case you can't tell (which is why l is a terrible name). Be aware that if the sum of the l values exceeds 255, you can't get a uint8 image, which is perhaps what you were starting with, without clipping.
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