Let numW be the maximum value that will be used for W, and numVA be the maximum value that will be used for VA, and numVAR be the maximum value that will be used for VAR. Then, before the loop that sets those variables,
Prline = zeros(1, numW);
Prw = zeros(1, numW);
Prsns = zeros(1, numW);
jQind = zeros(1, numVAR);
Sload = zeros(1, numVA);
By the way: if all of those variables are in the same loop and refer to the same IlineRect value, then calculate the common value only once:
absIline2 = abs(IlineRect)^2 / 2;
Then
Prline(W) = absIline2 * Rline;
Prw(W) = absIline2 * Rw;
and so on.
