I have 2 matrices, Y and P, both of size m by n. I need to implement the following equation:
I'm having an issue with the index changing between j and l.
My initial try was:
eq = 2*Y.*Y - Y.*P - Y.*P
However, this is wrong of course since the multiplication would be with the same indices. I was thinking I would have to expand the matrices into a third dimension to overcome this problem with an extra index and then run some similar code for the equation, but I don't really understand how to perform this expansion and how the code for the equation would look like afterwards.
If you know another solution than to use a 3D matrix, this would of course also be much appreciated.
If it helps, I need to sum over index i afterwards, so this will reduce the dimensions again afterwards.
To clarrify: i runs from 1 to m and j & l run from 1 to n.