» plot ( blackman(100) )
» help blackman

BLACKMAN Blackman window.
W = BLACKMAN(N) returns the N-point symmetric Blackman window
in a column vector.
W = BLACKMAN(N,SFLAG) generates the N-point Blackman window 
using SFLAG window sampling. SFLAG may be either 'symmetric' 
or 'periodic'. By default, 'symmetric' window sampling is used.