Spin Semiconductor

hello all, some very basic questions, sorry if this seems too trivial, I could not find an explicit explanation in the site : what is the general code that implements a FIR filter of order N : that is y(n) = a_0*x[n] + a_1*x[n-1] + ... + a_N*x[n-N] where y(n) is the output and x[n-i] is the delayed ...