Book Image

Learning SciPy for Numerical and Scientific Computing Second Edition - Second Edition

Book Image

Learning SciPy for Numerical and Scientific Computing Second Edition - Second Edition

Overview of this book

This book targets programmers and scientists who have basic Python knowledge and who are keen to perform scientific and numerical computations with SciPy.
Table of Contents (10 chapters)
9
Index

Convenience and test functions

All the convenience functions are designed to facilitate a computational environment where the user does not need to worry about relative errors. The functions seem to be pointless at first sight, but behind their codes, there are state-of-the-art ideas that offer faster and more reliable results.

We have convenience functions beyond the ones defined in the NumPy libraries to find the solutions of trigonometric functions in degrees (cosdg, sindg, tandg, and cotdg); to compute angles in radians from their expressions in degrees, minutes, and seconds (radian); common powers (exp2 for 2**x, and exp10 for 10**x); and common functions for small values of the variable (log1p for log(1 + x), expm1 for exp(x) - 1, and cosm1 for cos(x) - 1).

For instance, in the following code snippet, the log1p function computes the natural logarithm of 1 + x. Why not simply add 1 to the value of x and then take the logarithm instead? Let's compare:

>>> import numpy
&gt...