% Fourier Series 3D Representation
clear all, close all, clc
% set up a time vector
  t0=0; tf=.97;
  dt=(tf-t0)/500;
  t=[t0:dt:tf];
% Initialize the Fourier Series Expansion
  wave=zeros(size(t));
  Z=[];
% Compute each harmonic and add them up
  for n=1:2:41,
    harmonic=4 / (pi * n) * sin(4 * pi * n * t);
	wave=wave+harmonic;
	plot(wave)
     % Store each harmonic as a row in a matrix
     Z=[Z;wave];
  end
% Plot the 3-D picture
n=[1:2:41];
surf(t,n,Z)
xlabel('time')
ylabel('n')
zlabel('magnitude')
shading interp
axis([0 1 0 40 -2 2])
view(37.5,57)