rw=reshape(Rw(sp,hd,:)*L/(rho*g*B^2),[nfr,1]);
...
for pp = 1:hd
rwfff(:,pp) = rw(:,1)
end
There's nowhere that rw is apparently dependent upon anything excepting coming from an array Rw and the indices to it aren't shown.
But, given that it is a column vector of some value based on those unknown values, there doesn't appear any reason that rwfff woudn't be an array of size(length(rw),hd) when the loop is finished.
It would be more efficient to preallocate rwfff with
rwfff=zeros(length(rw),hd);
before starting the loop but for such a small array it won't be noticeable but in the slightest. For large arrays neglecting this can become a severe bottleneck.
