mathjs/docs/configuration.md

Configuration

Math.js contains a number of configuration options. Configuration can be set when creating a math.js instance, or later on using the function config. Available configuration options are:

• epsilon. The minimum relative difference used to test equality between two compared values. This value is used by all comparison functions. Default value is 1e-14.

• matrix. The default type of matrix output for functions. Available values are: 'matrix' (default) or 'array'. Where possible, the type of matrix output from functions is determined from the function input: An array as input will return an Array, a Matrix as input will return a Matrix. In case of no matrix as input, the type of output is determined by the option matrix. In case of mixed matrix inputs, a matrix will be returned always.

• number. The default type of numbers. This setting is used by functions like eval which cannot determine the correct type of output from the functions input. For most functions though, the type of output is determined from the the input: a number as input will return a number as output, a BigNumber as input returns a BigNumber as output. Available values are: 'number' (default) or 'bignumber'. BigNumbers have higher precision than the default numbers of JavaScript.

• precision. The maximum number of significant digits for bigNumbers. This setting only applies to BigNumbers, not to numbers. Default value is 20.

Examples

This section shows a number of configuration examples.

Default configuration

// load the library
var mathjs = require('mathjs');

// create an instance of math.js with default configuration
var math1 = mathjs();

// range will output a matrix
math1.range(0, 4); // Matrix [0, 1, 2, 3]

Configuration for matrices

// load the library
var mathjs = require('mathjs');

// create an instance of math.js with configuration options
var config = {
  matrix: 'array'
};
var math2 = mathjs(config);

// range will output an Array
math2.range(0, 4); // Array [0, 1, 2, 3]

// change configuration
math2.config({
  matrix: 'matrix'
});

// range will output a Matrix
math2.range(0, 4); // Matrix [0, 1, 2, 3]

Configuration for BigNumbers

// load the library
var mathjs = require('mathjs');

// use BigNumbers by default
var math3 = mathjs({
  number: 'bignumber',
  precision: 32
});

// parser will parse numbers as BigNumber now:
math3.eval('1 / 3'); // BigNumber, 0.33333333333333333333333333333333