function Dn=squarewave(n)
% This function creates the FS coefficiets for a squarewave.  This
% squarewave has a period of 3.  It is equal to 1 from -1/2 to 1/2 and zero
% from 1/2 to 2.5

ind=find(n~=0);
Dn(ind)=1/3*sin(pi/3*n(ind))./(pi/3*n(ind));

ind=find(n==0);
Dn(ind)=1/3;

return