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

Time for action – asserting almost equal


Imagine that you have two numbers that are almost equal. Let's use the assert_almost_equal() function to check whether they are equal:

  1. Call the function with low precision (up to 7 decimal places):

    print("Decimal 6", np.testing.assert_almost_equal(0.123456789, 0.123456780, decimal=7))

    Note that no exception is raised, as you can see in the following result:

    Decimal 6 None
    
  2. Call the function with higher precision (up to 8 decimal places):

    print("Decimal 7", np.testing.assert_almost_equal(0.123456789, 0.123456780, decimal=8))

    The result is as follows:

    Decimal 7
    Traceback (most recent call last):
    
      raise AssertionError(msg)
    AssertionError:
    Arrays are not almost equal
     ACTUAL: 0.123456789
     DESIRED: 0.12345678
    

What just happened?

We used the assert_almost_equal() function from the NumPy testing package to check whether 0.123456789 and 0.123456780 are equal for different decimal precisions.

Pop quiz – specifying decimal precision

Q1. Which parameter of the...