In response to several requests, this edition includes a description of a collection of C++ routines for implementing the TAS classification for volcanic rocks (p.33–39). As parts of the TAS classification require the use of the CIPW norm calculation, this code is also included.

The package is only intended as a basic development kit with which to write other programs suited to specific needs.

The source code is not included in the book but can be downloaded from the Cambridge University Press website – see section C.5, p.236.

INTRODUCTION

Wherever possible the code has been written in a style which is largely self-explanatory so that readers who are not experts in programming techniques should be able to follow what is happening and get the package working without too much trouble.

Data input

The package expects to read analyses in tab-delimited format in which each item in a row or line is separated from the next by a tab character (entered by the tab key from the keyboard). Each analysis is then one row of a table. Such data can easily be produced from virtually all spreadsheet and word-processing programs, by saving the data in text-only format, and database programs by saving the data in tab-delimited format. The first item of each row must be the specimen name, which can be up to 128 characters long, followed by up to 26 oxide values.