Question

Hey guys I'm trying to take fourier transform of function and I'm unable to plot it in matlab..The function I want to plot is mirror
Can anyone please help me !!

close all;
clear all;
clc
syms u
x = -2:0.001:2;
gauss = exp(-8.*x.^2);
plot(x, gauss);
rect = heaviside(x+0.5) - heaviside(x-0.5);
mirror = rect.*gauss;
figure(2); plot (x, mirror);
figure(3); plot(x, rect);

Answer 1

What is the problem ?

I don't have the heaviside function, so I defined it as
function yy= heaviside(x)
yy= zeros(size(x));
yy(x>=0)= 1;

and evaluated
clear all;
clc

x = -2:0.001:2;
gauss = exp(-8.*x.^2);
figure(1); plot(x, gauss); title('Gaussian');
rect = heaviside(x+0.5) - heaviside(x-0.5);

mirror = rect.*gauss;
figure(2); plot (x, mirror);title('Mirror');
figure(3); plot(x, rect); title('Rectangle');

Answer 2

Hi,
Actually I just need the Fourier transform of the mirror function of my code...COuld you please help me ?

Answer 3

clear all;
clc

dx= 0.001; Fs= 1/dx;
x = -2:dx:2;
N= floor(length(x)/2);
T= 4;
df= 1.0/T; frq= df*N;

gauss = exp(-8.*x.^2);

% 5 Hz sinusoid. Shows up at +5 Hz and -5 Hz
%gauss= 0.5*sin(2*pi*5*x);

%figure(1); plot(x, gauss); title('Gaussian');
rect = heaviside(x+0.5) - heaviside(x-0.5);

mirror = rect.*gauss;
%figure(2); plot (x, mirror);title('Mirror');
%figure(3); plot(x, rect); title('Rectangle');

MIRROR= fftshift(fft(mirror));

ff= -frq:df:frq;

figure(4); plot(ff,20*log10(abs(MIRROR)));

figure(5); plot(ff,20*log10(abs(MIRROR)));
title('POWER SPECTRUM');
axis([ -15 15 0 60]); grid on; shg;