Back ArrowExplore all kits

Scaling frequency axis in Fast Fourier Transform

share link

by Abdul Rawoof A R dot icon Updated: Mar 27, 2023

technology logo
technology logo

Solution Kit Solution Kit  

In Python, the FFT display shows frequency-based signals as generated from the FFT functions, and the x-axis shows the frequency while the y-axis shows the amplitude of the different spectral components. Its display can show signals with a logarithmic y-axis and a linear y-axis. 



The frequency range of an FFT result from banks on the sample rate frequency at which the input data points were evenly sampled, and the FFT results are data points in the frequency domain spaced at the sample rate frequency divided by the FFT length, from 0 or DC up to half the sample rate. A histogram is a graph in which each column represents a numeric variable, particularly one continuous and/or grouped. The Y-axis (vertical axis) generally represents the frequency count, while the X-axis (horizontal axis) generally represents the measured variable. 

  • NumPy - a Python library used for working with arrays. It has functions for working in the domain of linear algebra, Fourier transform, and matrices. 
  • Matplotlib - a comprehensive library for creating static, animated, and interactive visualizations in Python, making easy and hard things possible. It creates publication-quality plots. Also, it makes interactive figures that can zoom, pan, and update. 



Here is an example of how to scale the frequency axis in Fast Fourier Transform in Python: 

Fig: Preview of the output that you will get on running this code from your IDE.

Code

In this solution we're using NumPy and Matplotlib libraries.

How to properly scale frequency axis in Fast Fourier Transform?

PythondotLines of Code : 18dotLicense : Strong Copyleft (CC BY-SA 4.0)

Dependent Libraries : 
from numpy.fft import fft
from numpy import arange, linspace, sin, pi as π
from matplotlib import pyplot

def FFT(t, y):
    n = len(t)
    Δ = (max(t) - min(t)) / (n-1)
    k = int(n/2)
    f = arange(k) / (n*Δ)
    Y = abs(fft(y))[:k]
    return (f, Y)

t = linspace(-10, +10, num=1024)
y = sin(2*π * 5*t) + sin(2*π * t)
(f, Y) = FFT(t, y)
pyplot.plot(f, Y)
pyplot.show()

Instructions

Follow the steps carefully to get the output easily.

  1. Install PyCharm Community Edition on your computer.
  2. Open terminal and install the required libraries with following commands.
  3. Install NumPy - pip install numpy.
  4. Install Matplotlib - pip install matplotlib.
  5. Create a new Python file(eg: test.py).
  6. Copy the snippet using the 'copy' button and paste it into that file.
  7. Run the file using run button.


I hope you found this useful. I have added the link to dependent libraries, version information in the following sections.


I found this code snippet by searching for 'scale frequency axis in Fast Fourier Transform' in kandi. You can try any such use case!

Environment Tested

I tested this solution in the following versions. Be mindful of changes when working with other versions.

  1. The solution is created in PyCharm 2022.3.3.
  2. The solution is tested on Python 3.9.7.
  3. NumPy version 1.24.2.
  4. Matplotlib version 3.7.1.


Using this solution, we are able to scale frequency axis in Fast Fourier Transform in Python with simple steps. This process also facilities an easy way to use, hassle-free method to create a hands-on working version of code which would help us to scale frequency axis in Fast Fourier Transform in Python.

Dependent Libraries

numpyby numpy

Python doticonstar image 23755 doticonVersion:v1.25.0rc1doticon
License: Permissive (BSD-3-Clause)

The fundamental package for scientific computing with Python.

Support
    Quality
      Security
        License
          Reuse

            numpyby numpy

            Python doticon star image 23755 doticonVersion:v1.25.0rc1doticon License: Permissive (BSD-3-Clause)

            The fundamental package for scientific computing with Python.
            Support
              Quality
                Security
                  License
                    Reuse

                      matplotlibby matplotlib

                      Python doticonstar image 17559 doticonVersion:v3.7.1doticon
                      no licences License: No License (null)

                      matplotlib: plotting with Python

                      Support
                        Quality
                          Security
                            License
                              Reuse

                                matplotlibby matplotlib

                                Python doticon star image 17559 doticonVersion:v3.7.1doticonno licences License: No License

                                matplotlib: plotting with Python
                                Support
                                  Quality
                                    Security
                                      License
                                        Reuse

                                          You can also search for any dependent libraries on kandi like 'NumPy' and 'Matplotlib'.

                                          Support

                                          1. For any support on kandi solution kits, please use the chat
                                          2. For further learning resources, visit the Open Weaver Community learning page.


                                          See similar Kits and Libraries

                                          Open Weaver – Develop Applications Faster with Open Source

                                          kandi

                                          Community and Support

                                          Company

                                          Follow

                                          • © 2023 Open Weaver Inc.