# Asmar 2.3-7, plot details Fourier series arbitrary period
pulse:=(x,a,b)->piecewise(x<a,0,x<b,1,0);
f:=x->(1-x)*pulse(x,0,2)+(-1-x)*pulse(x,-2,0);
#plot(f(x),x=0..1);
sw1:=x->x-floor(x+1/2);
F:=x->f(4*sw1(x/4));
plot(F(x),x=-1..4,discont=true);