Recent content by luckycool

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    Using MATLAB to get the fourier transform of dirac delta function

    Hi, thanks again :) If I change from t(end)=2 to other value then U2(f) will change its amplitude if I use dt instead of length(t). But it's ok, I will check it with books. Do you know in which book or which section they discuss this topic?
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    Using MATLAB to get the fourier transform of dirac delta function

    Thanks so much. However, if I using this way for cosine function, then it doesn't work again. u2=1*cos(20*t); U2=fftshift(fft(u2))*dt; This time, when I change the time setting, the value of U2 will change. It's so strange.
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    Using MATLAB to get the fourier transform of dirac delta function

    Homework Statement Dear all, I have a problem when I using MATLAB to get the Fourier transform of dirac delta function. below is my code.Homework Equations clear all; clc; close all; % t=0:0.002:2; t=0:0.002:4; dt=t(2)-t(1); u=zeros(size(t)); pos0=find(t>=1,1); u(pos0)=1/dt...