Book Image

Learning SciPy for Numerical and Scientific Computing

By : Francisco J. Blanco-Silva
Book Image

Learning SciPy for Numerical and Scientific Computing

By: Francisco J. Blanco-Silva

Overview of this book

<p>It's essential to incorporate workflow data and code from various sources in order to create fast and effective algorithms to solve complex problems in science and engineering. Data is coming at us faster, dirtier, and at an ever increasing rate. There is no need to employ difficult-to-maintain code, or expensive mathematical engines to solve your numerical computations anymore. SciPy guarantees fast, accurate, and easy-to-code solutions to your numerical and scientific computing applications.<br /><br />"Learning SciPy for Numerical and Scientific Computing" unveils secrets to some of the most critical mathematical and scientific computing problems and will play an instrumental role in supporting your research. The book will teach you how to quickly and efficiently use different modules and routines from the SciPy library to cover the vast scope of numerical mathematics with its simplistic practical approach that's easy to follow.<br /><br />The book starts with a brief description of the SciPy libraries, showing practical demonstrations for acquiring and installing them on your system. This is followed by the second chapter which is a fun and fast-paced primer to array creation, manipulation, and problem-solving based on these techniques.<br /><br />The rest of the chapters describe the use of all different modules and routines from the SciPy libraries, through the scope of different branches of numerical mathematics. Each big field is represented: numerical analysis, linear algebra, statistics, signal processing, and computational geometry. And for each of these fields all possibilities are illustrated with clear syntax, and plenty of examples. The book then presents combinations of all these techniques to the solution of research problems in real-life scenarios for different sciences or engineering — from image compression, biological classification of species, control theory, design of wings, to structural analysis of oxides.</p>
Table of Contents (15 chapters)

Fortran


SciPy provides a simple way of including Fortran code – f2py. This is a utility shipped with the NumPy libraries, which is operative when distutils from SciPy are available. This is always the case when we install SciPy.

The f2py utility is supposed to run outside of Python, and it is used to create from any Fortran file, a Python module that can be easily called in our sessions. Under any *nix system, we call it from the terminal. Under Windows, we recommend to run it in the native terminal, or even better, through a cygwin session.

Before being compiled with f2py, any Fortran code needs to undergo three basic changes, as follows:

  • Removal of all allocations

  • Transformation of the whole program into a subroutine

  • If anything special needs to be passed to f2py, we must add it with the comment string "!f2py" or "cf2py"

Let us illustrate the process with a simple example. The following naïve subroutine, which we store in the primefactors.f file, performs a factorization in prime numbers for...