module.exports = function (math) { var util = require('../../util/index'), string = util.string; /** * Format a value of any type into a string. * * Syntax: * * math.format(value) * math.format(value, options) * math.format(value, precision) * math.format(value, fn) * * Where: * * {*} value The value to be formatted * {Object} options An object with formatting options. Available options: * {String} notation * Number notation. Choose from: * 'fixed' Always use regular number notation. * For example '123.40' and '14000000' * 'exponential' Always use exponential notation. * For example '1.234e+2' and '1.4e+7' * 'auto' (default) Regular number notation for numbers * having an absolute value between * `lower` and `upper` bounds, and uses * exponential notation elsewhere. * Lower bound is included, upper bound * is excluded. * For example '123.4' and '1.4e7'. * {Number} precision A number between 0 and 16 to round * the digits of the number. * In case of notations 'exponential' and * 'auto', `precision` defines the total * number of significant digits returned * and is undefined by default. * In case of notation 'fixed', * `precision` defines the number of * significant digits after the decimal * point, and is 0 by default. * {Object} exponential An object containing two parameters, * {Number} lower and {Number} upper, * used by notation 'auto' to determine * when to return exponential notation. * Default values are `lower=1e-3` and * `upper=1e5`. * Only applicable for notation `auto`. * {Function} fn A custom formatting function. Can be used to override the * built-in notations. Function `fn` is called with `value` as * parameter and must return a string. Is useful for example to * format all values inside a matrix in a particular way. * * Examples: * * math.format(6.4); // returns '6.4' * math.format(1240000); // returns '1.24e6' * math.format(1/3); // returns '0.3333333333333333' * math.format(1/3, 3); // returns '0.333' * math.format(21385, 2); // returns '21000' * math.format(12.071, {notation: 'fixed'}); // returns '12' * math.format(2.3, {notation: 'fixed', precision: 2}); // returns '2.30' * math.format(52.8, {notation: 'exponential'}); // returns '5.28e+1' * * See also: * * print * * @param {*} value Value to be stringified * @param {Object | Function | Number} [options] Formatting options * @return {String} str The formatted value */ math.format = function format (value, options) { var num = arguments.length; if (num !== 1 && num !== 2) { throw new math.error.ArgumentsError('format', num, 1, 2); } return string.format(value, options); }; };