plotdft.m

matlab在电力电子技术仿真中运用

function plotdft(x, fs)

%plots fft of x versus frequency for 0..fs/2
% where fs is the sampling frequency in Hz
% usage:  plotdft(x, fs)

N=length(x);							%set length
f=[0:fs/(N-1):fs/2];					%calculate frequency sample points
dft=abs(fft(x));						%calculate DFT

stem(f,dft(1:N/2));					%produce plot

axis([0, fs/2,0,max(dft)]);		%scale axis to keep them neat!
title('DFT   0..fs/2');				%finally, label every thing...
xlabel('frequency (Hz)');
ylabel('amplitude');



%David Phillips 09507351  
%Curtin Univeristy Linear systems 202
%23 October 2000