Dirichlet or periodic sinc function
y = diric(x,n)
The Dirichlet function, or periodic sinc function, is
for any nonzero integer n. This function has period 2π for n odd and period 4π for n even. Its peak value is 1, and its minimum value is -1 for n even. The magnitude of this function is (1/n) times the magnitude of the discrete-time Fourier transform of the n-point rectangular window.
If n is not a positive integer, diric gives the following error message:
Requires n to be a positive integer.