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 approximately equal


Let's take the numbers from the previous Time for action section and let the assert_approx_equal() function work on them:

  1. Call the function with low significance:

    print("Significance 8", np.testing.assert_approx_equal (0.123456789, 0.123456780,significant=8))

    The result is as follows:

    Significance 8 None
    
  2. Call the function with high significance:

    print("Significance 9", np.testing.assert_approx_equal (0.123456789, 0.123456780, significant=9))

    The function raises an AssertionError:

    Significance 9
    Traceback (most recent call last):
      ...
        raise AssertionError(msg)
    AssertionError:
    Items are not equal to 9 significant digits:
     ACTUAL: 0.123456789
     DESIRED: 0.12345678
    

What just happened?

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