Matlab for the Bartlett Window:

In matlab, a length $M$ Bartlett window is designed by the statement

w = bartlett(M);

This is equivalent, for odd $M$ , to

w = 2*(0:(M-1)/2)/(M-1);
w = [w w((M-1)/2:-1:1)]';

Note that, in contrast to the hanning function, but like the hann function, bartlett explicitly includes zeros at its endpoints:

>> bartlett(3)
ans =
     0
     1
     0

The triang function in Matlab implements the triangular window corresponding to the hanning case:

>> triang(3)
ans =
     0.5000
     1.0000
     0.5000