#Calc of Talbot PAtterns # # # N=21 d=2.0 sigma=1.0 cospart(x,n) = cos ( ( pi*n/(2*sigma))*(n - 2*x/d) ) sinpart(x,n) = sin ( ( pi*n/(2*sigma))*(n - 2*x/d) ) # sumcos(x,n) = (-N<n) ? ( cospart(x,n) + sumcos(x,n-1) ):0 sumsin(x,n) = (-N<n) ? ( sinpart(x,n) + sumsin(x,n-1) ):0 # I(x)=(sumcos(x,N))**2 + (sumsin(x,N))**2 plot [-5:5] I(x)