%==================================================================
% Name: flt.m
% This program can be used to obvious the relationship
% between the zero-pole location and the time and frequency domain
% characteristics of the rectangular pulse.
%==================================================================
clear,close all;
a=-0:0.4:5;
b=-20:0.4:20;					
[a,b]=meshgrid(a,b);
c=a+i*b;						%確定繪圖區(qū)域
c=(1-exp(-2*(c+eps)))./(c+eps);
c=abs(c);						%計算拉普拉斯變換

subplot(2,1,1)
mesh(a,b,c);					%繪制曲面圖
surf(a,b,c);
view(-60,20)					%調(diào)整觀察視角
axis([-0,5,-20,20,0,2]);
title('The Laplace transform of the rectangular pulse');
%colormap(hsv);
w=-20:0.1:20;
Fw=(2*sin(w+eps).*exp(i*(w+eps)))./(w+eps);
subplot(2,1,2);plot(w,abs(Fw))
title('The Fourier transform of the rectangular pulse')
xlabel('frequence w')
%=========================================================