function an=proj(x)
% this function only makes sense when called from a.m or b.m
% It computes the integrand that is then integrated to compute a Fourier 
% coefficient.
% 
% It returns FUNC_NAME(x) .* TRIG_NAME(M*x)
% where FUNC_NAME, TRIG_NAME, and M are global variables set in a.m or b.m

global M;
global FUNC_NAME;
global TRIG_NAME;	
an=eval([FUNC_NAME,'(x) .* ',TRIG_NAME,'(M*x)']);