close all
clear all 
clc

load('exercise2.mat') % defines t, x, T
N = length(x);
X = fftshift(T*fft(x));
om = (-round((N-1)/2):round(N/2)-1) *2*pi/(N*T);          

figure
subplot(2,1,1)
plot(t,x)
grid
xlabel('t')
ylabel('x(t)')
title('signal')
subplot(2,1,2)
semilogy(om,abs(X))
grid
xlabel('\omega')
ylabel('X(\omega)')
axis([0 max(om) 1e-3 1e4])
title('Fourier transform')

% printing figure in png format
set(gcf,'PaperUnits','inches','PaperPosition',[0 0 6 4.5])
print -dpng exercise2.png -r100