This is because writing arguments like this:
matlabpool open 2
is the same as passing the strings 'open' and '2' to the matlabpool function, i.e. the equivalent to
matlabpool('open','2')
What you can do is to call matlabpool like this:
matlabpool('open', num2str(features('numCores')))
Possibly you can also pass the number of cores directly, but since I do not have parallell computing toolbox I can't test it, like so:
matlabpool('open', features('numCores'))
