mathjs/lib/function/arithmetic/exp.js

Math.js is an extensive math library for JavaScript and Node.js. It features a flexible expression parser with support for symbolic computation, comes with a large set of built-in functions and constants, and offers an integrated solution to work with dif

'use strict';

var deepMap = require('../../utils/collection/deepMap');

function factory(type, config, load, typed) {
  /**
   * Calculate the exponent of a value.
   * For matrices, the function is evaluated element wise.
   *
   * Syntax:
   *
   *    math.exp(x)
   *
   * Examples:
   *
   *    math.exp(2)                  // returns number 7.3890560989306495
   *    math.pow(math.e, 2)          // returns number 7.3890560989306495
   *    math.log(math.exp(2))        // returns number 2
   *
   *    math.exp([1, 2, 3])
   *    // returns Array [
   *    //   2.718281828459045,
   *    //   7.3890560989306495,
   *    //   20.085536923187668
   *    // ]
   *
   * See also:
   *
   *    expm1, log, pow
   *
   * @param {number | BigNumber | Complex | Array | Matrix} x  A number or matrix to exponentiate
   * @return {number | BigNumber | Complex | Array | Matrix} Exponent of `x`
   */
  var exp = typed('exp', {
    'number': Math.exp,
    'Complex': function Complex(x) {
      return x.exp();
    },
    'BigNumber': function BigNumber(x) {
      return x.exp();
    },
    'Array | Matrix': function ArrayMatrix(x) {
      // TODO: exp(sparse) should return a dense matrix since exp(0)==1
      return deepMap(x, exp);
    }
  });
  exp.toTex = {
    1: "\\exp\\left(${args[0]}\\right)"
  };
  return exp;
}

exports.name = 'exp';
exports.factory = factory;