function y=sqw(t,T,d)
%SQW Square wave generation
% sqw(t,T,d) generates a square wave of period T
% that oscillates between 0 and 1 for the time elements
% in vector t. The duty cycled determines the percentage
% of time that the square wave is "on" (equal to 1).
%
%EXAMPLE
%
% The following code will produce a square wave of
% period 8. The duty cycle is 25, representing 25%, determines
% that the square wave will be "on" (equal to 1) during the
% first 25% of its period, then "off" (equal to 0) during
% the remaining 75% of the period.
%
% t=linspace(0,24,1000);
% y=sqw(t,8,25);
% plot(t,y)
% set(gca,'xtick',0:24)
% axis tight
% grid
%
tmp=mod(t,T);
w0=T*d/100;
y=(tmp