%
% Written by:
% --
% John L. Weatherwax                2009-04-21
%
% email: wax@alum.mit.edu
%
% Please send comments and especially bug reports to the
% above email address.
%
%-----

close all; clc; clear; 

% EPage 137

nt = 512;
T = 1;
dt = T/nt;
t = 0:dt:(T-dt);
df = 1/T;
fmax = nt/(2*T);
f = 0:df:df*(nt/2-1);

f_1 = 30;
y = 32 * sin( 2*pi*f_1*t ).^5;

Y = fft(y);
Ys = zeros(1,nt/2);
Ys(1:nt/2) = (2/nt)*Y(1:nt/2);
plot( f, abs(Ys));
xlabel('frequency Hz'); ylabel('abs(DFT)'); title('DFT sin^5');
grid('on');

%saveas( gcf, '../../WriteUp/Graphics/Chapter7/c_7_p_13_sin5_plot.eps', 'epsc' );

close all; 

% 
y = 32 * sin( 2*pi*f_1*t ).^6;

Y = fft(y);
Ys = zeros(1,nt/2);
Ys(1:nt/2) = (2/nt)*Y(1:nt/2);
plot( f, abs(Ys));
xlabel('frequency Hz'); ylabel('abs(DFT)'); title('DFT sin^6');
grid('on');

%saveas( gcf, '../../WriteUp/Graphics/Chapter7/c_7_p_13_sin6_plot.eps', 'epsc' );