FFT computation (fft) in SciPy - Mini Project: Build & Apply

FFT computation (fft)

📖 Scenario: You have recorded a simple signal that changes over time. You want to find out the main frequencies in this signal using FFT (Fast Fourier Transform).

🎯 Goal: Build a program that computes the FFT of a signal and shows the frequency components.

📋 What You'll Learn

Create a list of signal values representing a simple wave

Set the sampling rate of the signal

Compute the FFT of the signal using scipy.fft.fft

Print the absolute values of the FFT result

💡 Why This Matters

🌍 Real World

FFT is used in audio processing, image analysis, and many fields to find hidden frequencies in signals.

💼 Career

Understanding FFT helps in roles like data analyst, signal processing engineer, and any job involving time series data.

1

Create the signal data

Create a list called signal with these exact values: 0.0, 1.0, 0.0, -1.0 representing one cycle of a wave.

SciPy

# Create the signal list with values 0.0, 1.0, 0.0, -1.0
# Your code here

Need a hint?

Use square brackets to create a list and separate values with commas.

2

Set the sampling rate

Create a variable called sampling_rate and set it to 4 to represent 4 samples per second.

SciPy

signal = [0.0, 1.0, 0.0, -1.0]
# Set sampling_rate to 4
# Your code here

Need a hint?

Sampling rate is how many samples are taken per second.

3

Compute the FFT

Import fft from scipy.fft and create a variable called fft_result by applying fft(signal).

SciPy

signal = [0.0, 1.0, 0.0, -1.0]
sampling_rate = 4
# Import fft and compute fft_result
# Your code here

Need a hint?

Use from scipy.fft import fft to import the FFT function.

4

Print the FFT output

Print the absolute values of fft_result using print(abs(fft_result)) to see the strength of each frequency.

SciPy

from scipy.fft import fft

signal = [0.0, 1.0, 0.0, -1.0]
sampling_rate = 4

fft_result = fft(signal)
# Print the absolute values of fft_result
# Your code here

Need a hint?

The output shows the strength of each frequency component in the signal.