Question

如何用matlab导入数据进行FFT频

Answer 1

给你一个例子，来说明如何导入数据。

Fs = 1000; 

T = 1/Fs; 

L = 1000; 

t = (0:L-1)*T; 

x = 0.7*sin(2*pi*50*t) + sin(2*pi*120*t); 

y = x + 2*randn(size(t));  

NFFT = 2^nextpow2(L); 

Y = fft(y,NFFT)/L;

f = Fs/2*linspace(0,1,NFFT/2+1);

plot(f,2*abs(Y(1:NFFT/2+1))) 

title('Single-Sided Amplitude Spectrum of y(t)')

xlabel('Frequency (Hz)')

ylabel('|Y(f)|')