The code attached works in Octave and i need it to work in matlab but i cannot find a suitable replacement for the increment operator used in the line "indx = ++nCount(nS)". The desired out put from the code is meant to be a cell array Ivals which is 63*2 with each of the cells in the first column containing a 1 row array of all the pixel intensities that have the same s value. This row ges from those with sMin to those with s value sMax. The second column should be the designation in the array e.g. 319 501. Any help would be greatly appreciated, even if it is a complete rethink of what i have done.