Book Image

Mathematica Data Analysis

By : Sergiy Suchok
Book Image

Mathematica Data Analysis

By: Sergiy Suchok

Overview of this book

There are many algorithms for data analysis and it’s not always possible to quickly choose the best one for each case. Implementation of the algorithms takes a lot of time. With the help of Mathematica, you can quickly get a result from the use of a particular method, because this system contains almost all the known algorithms for data analysis. If you are not a programmer but you need to analyze data, this book will show you the capabilities of Mathematica when just few strings of intelligible code help to solve huge tasks from statistical issues to pattern recognition. If you're a programmer, with the help of this book, you will learn how to use the library of algorithms implemented in Mathematica in your programs, as well as how to write algorithm testing procedure. With each chapter, you'll be more immersed in the special world of Mathematica. Along with intuitive queries for data processing, we will highlight the nuances and features of this system, allowing you to build effective analysis systems. With the help of this book, you will learn how to optimize the computations by combining your libraries with the Mathematica kernel.
Table of Contents (15 chapters)
Mathematica Data Analysis
Credits
About the Author
About the Reviewer
www.PacktPub.com
Preface
Index

Controlling data completeness


In practice, it often happens that data is missing for some reason. If you take Mathematica's data about the countries of the world, not all of them will have updated information on population, GDP, and other parameters. In order to check the data for completeness, you can use the Missing function:

This formula computes how many countries do not contain the information of the PopulationGrowth parameter. The Map function substitutes as an argument of the CountryData function values for all the countries that are stored in the database. The _Missing filter computes only those countries whose information is missing.

Note

There is also a short form of the Map - Map[f,{a,b,c}] function that can be written as f/@{a,b,c}. The result in both cases will be {f[a],f[b],f[c]}.

To prevent missing data that affects statistics, you can use the DeleteCases function:

Thus, all the data used by Mathematica to find the PopulationGrowth parameter values and that fail to do this will...