Book Image

NumPy: Beginner's Guide

By : Ivan Idris
Book Image

NumPy: Beginner's Guide

By: Ivan Idris

Overview of this book

Table of Contents (21 chapters)
NumPy Beginner's Guide Third Edition
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
NumPy Functions' References
Index

Fourier analysis


Signals in the real world often have a periodic nature. A commonly used tool to deal with these signals is the Discrete Fourier transform (see https://en.wikipedia.org/wiki/Discrete-time_Fourier_transform). The Discrete Fourier transform is a transformation from the time domain into the frequency domain, that is, the linear decomposition of a periodic signal into sine and cosine functions with various frequencies:

Functions for Fourier transforms can be found in the scipy.fftpack module (NumPy also has its own Fourier package numpy.fft). Included in the package are Fast Fourier transforms, differential and pseudo-differential operators, as well as several helper functions. MATLAB users will be pleased to know that a number of functions in the scipy.fftpack module have the same name as their MATLAB counterparts, and a similar function as their MATLAB equivalents.