MeatAxe: maketab - Calculate Arithmetic Tables

MeatAxe 2.4

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maketab - Calculate Arithmetic Tables

## Command Line

    maketab Field

Field
  The field order.

## Output Files

pXXX.zzz
  Arithmetic tables for GF(XXX).

## Description

Attention:
  This program is no longer needed. Arithmetic tables are calculated automatically when needed.

This program generates the lookup tables used by the finite field arithmetic. Tables are stored in a file (one file for each field) which is loaded by the MeatAxe applications at run-time. The argument, Field, must be a positive integer (a prime power, actually). The upper limit for the field order depends on which version of the arithmetic you are using. The arithmetic version is chosen at compile-time.

The standard version of MAKETAB creates table files for fields up to GF(256). The output file is named "pXXX.zzz", where XXX is the field order. The size of this file is approximately 130 KBytes and does not depend on the field order. For the `big' version, the largest possible field is GF(65536), and the output file is named "pXXXXX.zzz", where XXXXX is the field order. This file is usually (i.e., for comparable field orders) much smaller than the standard version file, but its size increases linearly with the field order.

The table file is needed whenever a program performs finite field operations, i.e., when working with matrices. The programs look for the table file first in the current directory and then, if it is not there, in the library directory. Thus, table files for the most commonly used fields can be kept in the library, and additional table files can be created in the current directory when they are needed. Usually, the name of the library directory is defined at compile-time, but this may be changed at any time by defining the environment variable MTXLIB.