MATLAB: How to divide array, that result would be like dividing columns

arraydivision

Hello, Can somebody give a little explanation about matrix division? For example there are two arrays a (100×5) and b (100×5). If I try to left divide two columns;

c=a(:,1)\b(:,1);

Result is c(1×1), However if I try to divide both arrays:

C=a\b;

Result is c(5×5), why it is not c(1×5)? As I understand it is different when dividing columns vs dividing matrix.

Best Answer

All combination of columns are used.

a(:,1)\b(:,1) a(:,1)\b(:,2) a(:,1)\b(:,3) ...
a(:,2)\b(:,1) a(:,2)\b(:,2) a(:,2)\b(:,3) ...

You could do

arrayfun(@(COL) A(:,COL)\B(:,COL), 1:size(A,2))

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Best Answer

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