Check the number of arguments to a function

Prettify checking the number of arguments to a function.

nargchk is used almost exclusively in one way:

error(nargchk(minargs, maxargs, nargin, 'struct'));

The third and fourth arguments are always the same, and you always wrap it in an error call.

This stupidly simple function saves you typing, and prettifies your code by wrapping the above line into something more readable, namely

CheckNumberArgs(minargs, maxargs);