Book Image

Scientific Computing with Python 3

By : Claus Führer, Jan Erik Solem, Olivier Verdier
Book Image

Scientific Computing with Python 3

By: Claus Führer, Jan Erik Solem, Olivier Verdier

Overview of this book

Python can be used for more than just general-purpose programming. It is a free, open source language and environment that has tremendous potential for use within the domain of scientific computing. This book presents Python in tight connection with mathematical applications and demonstrates how to use various concepts in Python for computing purposes, including examples with the latest version of Python 3. Python is an effective tool to use when coupling scientific computing and mathematics and this book will teach you how to use it for linear algebra, arrays, plotting, iterating, functions, polynomials, and much more.
Table of Contents (23 chapters)
Scientific Computing with Python 3
Credits
About the Authors
About the Reviewer
www.PacktPub.com
Acknowledgement
Preface
References

Basic plotting


The standard plotting function is plot. Calling plot(x,y) creates a figure window with a plot of y as a function of x. The input arguments are arrays (or lists) of equal length. It is also possible to use plot(y), in which case the values in y will be plotted against their index, that is, plot(y) is a short form of plot(range(len(y)),y).

Here is an example that shows how to plot sin(x) for x ϵ [-2π, 2π]  using 200 sample points and sets markers at every fourth point:

# plot sin(x) for some interval
x = linspace(-2*pi,2*pi,200)
plot(x,sin(x))

# plot marker for every 4th point
samples = x[::4]
plot(samples,sin(samples),'r*')

# add title and grid lines
title('Function sin(x) and some points plotted')
grid()

The result is shown in the following figure (Figure 6.1):

Figure 6.1: A plot of the function sin(x) with grid lines shown.

As you can see, the standard plot is a solid blue curve. Each axis gets automatically scaled to fit...