%
%  hw00code.m -- djm -- 04 jan 2009
%

clear

%  interval (-L < x < +L)
L = 1;

%  parameters
Nterms = 15;  Npts = max(4*Nterms,256);

%  vector of plotting points
dx = 2*L/Npts;  x = -L:dx:L;

%  summation loop
Ssum = 0;
%  j = 1, 2 ... Nterms
for k = 1:1:Nterms
    Ssum = Ssum + (1/(2*k-1))*sin((2*k-1)*pi*x);
end
Ssum = (4/pi)*Ssum;

%  make a plot
%
%  initialize a figure
figure(1);  clf

%  plot red line
plot([-L 0 0 L],[-1 -1 1 1],'r');

%  multiple plots:  type "help hold" at matlab prompt
hold on

%  plot sum with points (thick curve for emphasis)
plot(x,Ssum,'b','linewidth',2);
if(Npts<=1024)
    plot(x,Ssum,'k.');
end

%  add info
title(['\bf fourier series (example p299):  k=1 to ' num2str(Nterms) ' terms'],'fontsize',14)
xlabel('\bf x-axis','fontsize',12)
ylabel('\bf partial sum, S_{2N-1}(x)','fontsize',12)