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### FFT Magnitude and Phase Spectrum using MATLAB

## MATLAB Code

clc;

clear;

close all;

% Parameters

fs = 100; % Sampling frequency

t = 0:1/fs:1-1/fs; % Time vector

% Signal definition

x = cos(2*pi*15*t - pi/4) - sin(2*pi*40*t);

% Compute Fourier Transform

y = fft(x);

z = fftshift(y);

% Frequency vector

ly = length(y);

f = (-ly/2:ly/2-1)/ly*fs;

% Compute phase

phase = angle(z);

% Plot magnitude of the Fourier Transform

figure;

subplot(2, 1, 1);

stem(f, abs(z), 'b');

xlabel('Frequency (Hz)');

ylabel('|y|');

title('Magnitude of Fourier Transform');

grid on;

% Plot phase of the Fourier Transform

subplot(2, 1, 2);

stem(f, phase, 'b');

xlabel('Frequency (Hz)');

ylabel('Phase (radians)');

title('Phase of Fourier Transform');

grid on;

## Output

## Copy the MATLAB Code from here

### Parent Topics

Fourier Series and Fourier TransformFourier TransformMATLAB

Fourier Series and Fourier TransformFourier TransformMATLAB

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