MATLAB code which implements an FFT algorithm

[ylscqu]

refer the help,there are function for FFT

 

[sajaown]

matlab code for fft

Examples

A common use of Fourier transforms is to find the frequency components of a signal buried in a noisy time domain signal. Consider data sampled at 1000 Hz. Form a signal containing a 50 Hz sinusoid of amplitude 0.7 and 120 Hz sinusoid of amplitude 1 and corrupt it with some zero-mean random noise:

Fs = 1000; % Sampling frequency
T = 1/Fs; % Sample time
L = 1000; % Length of signal
t = (0:L-1)*T; % Time vector
% Sum of a 50 Hz sinusoid and a 120 Hz sinusoid
x = 0.7*sin(2*pi*50*t) + sin(2*pi*120*t);
y = x + 2*randn(size(t)); % Sinusoids plus noise
plot(Fs*t(1:50),y(1:50))
title('Signal Corrupted with Zero-Mean Random Noise')
xlabel('time (milliseconds)')

NFFT = 2^nextpow2(L); % Next power of 2 from length of y
Y = fft(y,NFFT)/L;
f = Fs/2*linspace(0,1,NFFT/2);

% Plot single-sided amplitude spectrum.
plot(f,2*abs(Y(1:NFFT/2)))
title('Single-Sided Amplitude Spectrum of y(t)')
xlabel('Frequency (Hz)')
ylabel('|Y(f)|')

 

[mahaju]

matlab fft code

Thank you for your code but I an need of a MATLAB code which actually implements an FFT algorithm, rather than a built in library function. Please send me one if you have it.
Thank you

 

[Aya2002]

fft in matlab

hi dear

see this file. It contain the complete program for the dft algorithm in matlab

enjoy

 

[venuscrossing]

fft code in matlab

can anyone give the code for IFFT? Thank you in advance...

 

[Aya2002]

fft code matlab

see this link:

 

[Rafika]

Re: fft code matlab

see this link:

thank you sir for prescriptively ............. grown advence

- - - Updated - - -

hi dear

see this file. It contain the complete program for the dft algorithm in matlab

enjoy

My scientific work is being completed, and chose this field in research,
and I really needed this post ...
thank you so much....