dehorsley / sheetmult

Sheet multiplication in MATLAB C mex

Sheetmult

NOTE: you probably don't want to use this anymore. MATLAB's JIT can now do just as good a job (if not better) as the in place version without using nasty undocumented APIs.

This is a MATLAB C mex program to multiply two "sheets" (3D arrays) together. Eg:

for i=1:N
    P(:,i) = A'*R(:,:,i);
end

where all arrays are the appropriate size.

sheetmult creates a new array for the resulting product, however there is an in-place version (sheetmultip) which places the result back in the A matrix. This uses some undocumented features of MATLAB to work well with the copy-on-write mechanism so, due to the nature of these APIs, this may break in future versions or crash MATLAB. (Tested on 2014a)