aaFrequency counter

If we need it for residue PCA
pca_loop.m / coordinatePCA.m

I didn’t change anything in pca_loop.m but wrote coordinatePCA.m, which
is a slightly modified version of pca_loop
Normalization of residuePCA with aa frequency

You can use residuePCA with the aa frequency instead of the count and
decide to normalize the data by removing the average frequency of amino
acid in uniprot (normalize = 2).
Loop over the sectorDB for coordinatePCA

Output is a 3x numel(sectorDB) keeping track of the eigenvalues of each
sector.
Playing with coordinate PCA