1412 lines
28 KiB
JavaScript
1412 lines
28 KiB
JavaScript
'use strict';
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/**
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*
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* This class allows the manipulation of complex numbers.
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* You can pass a complex number in different formats. Either as object, double, string or two integer parameters.
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*
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* Object form
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* { re: <real>, im: <imaginary> }
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* { arg: <angle>, abs: <radius> }
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* { phi: <angle>, r: <radius> }
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*
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* Array / Vector form
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* [ real, imaginary ]
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*
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* Double form
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* 99.3 - Single double value
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*
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* String form
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* '23.1337' - Simple real number
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* '15+3i' - a simple complex number
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* '3-i' - a simple complex number
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*
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* Example:
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*
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* const c = new Complex('99.3+8i');
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* c.mul({r: 3, i: 9}).div(4.9).sub(3, 2);
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*
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*/
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const cosh = Math.cosh || function (x) {
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return Math.abs(x) < 1e-9 ? 1 - x : (Math.exp(x) + Math.exp(-x)) * 0.5;
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};
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const sinh = Math.sinh || function (x) {
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return Math.abs(x) < 1e-9 ? x : (Math.exp(x) - Math.exp(-x)) * 0.5;
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};
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/**
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* Calculates cos(x) - 1 using Taylor series if x is small (-¼π ≤ x ≤ ¼π).
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*
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* @param {number} x
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* @returns {number} cos(x) - 1
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*/
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const cosm1 = function (x) {
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const b = Math.PI / 4;
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if (-b > x || x > b) {
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return Math.cos(x) - 1.0;
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}
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/* Calculate horner form of polynomial of taylor series in Q
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let fac = 1, alt = 1, pol = {};
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for (let i = 0; i <= 16; i++) {
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fac*= i || 1;
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if (i % 2 == 0) {
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pol[i] = new Fraction(1, alt * fac);
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alt = -alt;
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}
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}
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console.log(new Polynomial(pol).toHorner()); // (((((((1/20922789888000x^2-1/87178291200)x^2+1/479001600)x^2-1/3628800)x^2+1/40320)x^2-1/720)x^2+1/24)x^2-1/2)x^2+1
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*/
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const xx = x * x;
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return xx * (
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xx * (
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xx * (
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xx * (
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xx * (
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xx * (
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xx * (
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xx / 20922789888000
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- 1 / 87178291200)
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+ 1 / 479001600)
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- 1 / 3628800)
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+ 1 / 40320)
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- 1 / 720)
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+ 1 / 24)
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- 1 / 2);
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};
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const hypot = function (x, y) {
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x = Math.abs(x);
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y = Math.abs(y);
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// Ensure `x` is the larger value
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if (x < y) [x, y] = [y, x];
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// If both are below the threshold, use straightforward Pythagoras
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if (x < 1e8) return Math.sqrt(x * x + y * y);
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// For larger values, scale to avoid overflow
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y /= x;
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return x * Math.sqrt(1 + y * y);
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};
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const parser_exit = function () {
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throw SyntaxError('Invalid Param');
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};
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/**
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* Calculates log(sqrt(a^2+b^2)) in a way to avoid overflows
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*
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* @param {number} a
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* @param {number} b
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* @returns {number}
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*/
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function logHypot(a, b) {
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const _a = Math.abs(a);
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const _b = Math.abs(b);
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if (a === 0) {
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return Math.log(_b);
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}
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if (b === 0) {
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return Math.log(_a);
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}
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if (_a < 3000 && _b < 3000) {
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return Math.log(a * a + b * b) * 0.5;
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}
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/* I got 4 ideas to compute this property without overflow:
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*
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* Testing 1000000 times with random samples for a,b ∈ [1, 1000000000] against a big decimal library to get an error estimate
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*
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* 1. Only eliminate the square root: (OVERALL ERROR: 3.9122483030951116e-11)
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Math.log(a * a + b * b) / 2
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*
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*
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* 2. Try to use the non-overflowing pythagoras: (OVERALL ERROR: 8.889760039210159e-10)
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const fn = function(a, b) {
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a = Math.abs(a);
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b = Math.abs(b);
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let t = Math.min(a, b);
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a = Math.max(a, b);
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t = t / a;
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return Math.log(a) + Math.log(1 + t * t) / 2;
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};
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* 3. Abuse the identity cos(atan(y/x) = x / sqrt(x^2+y^2): (OVERALL ERROR: 3.4780178737037204e-10)
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Math.log(a / Math.cos(Math.atan2(b, a)))
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* 4. Use 3. and apply log rules: (OVERALL ERROR: 1.2014087502620896e-9)
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Math.log(a) - Math.log(Math.cos(Math.atan2(b, a)))
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*/
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a = a * 0.5;
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b = b * 0.5;
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return 0.5 * Math.log(a * a + b * b) + Math.LN2;
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}
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const P = { 're': 0, 'im': 0 };
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const parse = function (a, b) {
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const z = P;
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if (a === undefined || a === null) {
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z['re'] =
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z['im'] = 0;
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} else if (b !== undefined) {
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z['re'] = a;
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z['im'] = b;
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} else
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switch (typeof a) {
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case 'object':
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if ('im' in a && 're' in a) {
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z['re'] = a['re'];
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z['im'] = a['im'];
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} else if ('abs' in a && 'arg' in a) {
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if (!isFinite(a['abs']) && isFinite(a['arg'])) {
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return Complex['INFINITY'];
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}
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z['re'] = a['abs'] * Math.cos(a['arg']);
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z['im'] = a['abs'] * Math.sin(a['arg']);
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} else if ('r' in a && 'phi' in a) {
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if (!isFinite(a['r']) && isFinite(a['phi'])) {
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return Complex['INFINITY'];
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}
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z['re'] = a['r'] * Math.cos(a['phi']);
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z['im'] = a['r'] * Math.sin(a['phi']);
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} else if (a.length === 2) { // Quick array check
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z['re'] = a[0];
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z['im'] = a[1];
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} else {
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parser_exit();
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}
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break;
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case 'string':
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z['im'] = /* void */
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z['re'] = 0;
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const tokens = a.replace(/_/g, '')
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.match(/\d+\.?\d*e[+-]?\d+|\d+\.?\d*|\.\d+|./g);
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let plus = 1;
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let minus = 0;
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if (tokens === null) {
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parser_exit();
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}
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for (let i = 0; i < tokens.length; i++) {
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const c = tokens[i];
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if (c === ' ' || c === '\t' || c === '\n') {
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/* void */
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} else if (c === '+') {
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plus++;
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} else if (c === '-') {
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minus++;
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} else if (c === 'i' || c === 'I') {
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if (plus + minus === 0) {
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parser_exit();
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}
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if (tokens[i + 1] !== ' ' && !isNaN(tokens[i + 1])) {
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z['im'] += parseFloat((minus % 2 ? '-' : '') + tokens[i + 1]);
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i++;
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} else {
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z['im'] += parseFloat((minus % 2 ? '-' : '') + '1');
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}
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plus = minus = 0;
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} else {
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if (plus + minus === 0 || isNaN(c)) {
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parser_exit();
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}
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if (tokens[i + 1] === 'i' || tokens[i + 1] === 'I') {
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z['im'] += parseFloat((minus % 2 ? '-' : '') + c);
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i++;
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} else {
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z['re'] += parseFloat((minus % 2 ? '-' : '') + c);
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}
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plus = minus = 0;
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}
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}
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// Still something on the stack
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if (plus + minus > 0) {
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parser_exit();
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}
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break;
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case 'number':
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z['im'] = 0;
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z['re'] = a;
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break;
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default:
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parser_exit();
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}
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if (isNaN(z['re']) || isNaN(z['im'])) {
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// If a calculation is NaN, we treat it as NaN and don't throw
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//parser_exit();
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}
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return z;
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};
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/**
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* @constructor
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* @returns {Complex}
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*/
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function Complex(a, b) {
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if (!(this instanceof Complex)) {
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return new Complex(a, b);
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}
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const z = parse(a, b);
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this['re'] = z['re'];
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this['im'] = z['im'];
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}
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Complex.prototype = {
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're': 0,
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'im': 0,
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/**
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* Calculates the sign of a complex number, which is a normalized complex
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*
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* @returns {Complex}
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*/
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'sign': function () {
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const abs = hypot(this['re'], this['im']);
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return new Complex(
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this['re'] / abs,
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this['im'] / abs);
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},
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/**
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* Adds two complex numbers
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*
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* @returns {Complex}
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*/
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'add': function (a, b) {
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const z = parse(a, b);
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const tInfin = this['isInfinite']();
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const zInfin = !(isFinite(z['re']) && isFinite(z['im']));
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if (tInfin || zInfin) {
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if (tInfin && zInfin) {
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// Infinity + Infinity = NaN
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return Complex['NAN'];
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}
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// Infinity + z = Infinity { where z != Infinity }
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return Complex['INFINITY'];
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}
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return new Complex(
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this['re'] + z['re'],
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this['im'] + z['im']);
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},
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/**
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* Subtracts two complex numbers
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*
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* @returns {Complex}
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*/
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'sub': function (a, b) {
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const z = parse(a, b);
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const tInfin = this['isInfinite']();
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const zInfin = !(isFinite(z['re']) && isFinite(z['im']));
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if (tInfin || zInfin) {
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if (tInfin && zInfin) {
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// Infinity - Infinity = NaN
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return Complex['NAN'];
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}
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// Infinity - z = Infinity { where z != Infinity }
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return Complex['INFINITY'];
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}
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return new Complex(
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this['re'] - z['re'],
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this['im'] - z['im']);
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},
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/**
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* Multiplies two complex numbers
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*
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* @returns {Complex}
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*/
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'mul': function (a, b) {
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const z = parse(a, b);
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const tInfin = this['isInfinite']();
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const zInfin = !(isFinite(z['re']) && isFinite(z['im']));
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const tIsZero = this['re'] === 0 && this['im'] === 0;
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const zIsZero = z['re'] === 0 && z['im'] === 0;
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// Infinity * 0 = NaN
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if (tInfin && zIsZero || zInfin && tIsZero) {
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return Complex['NAN'];
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}
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// Infinity * z = Infinity { where z != 0 }
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if (tInfin || zInfin) {
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return Complex['INFINITY'];
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}
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// Shortcut for real values
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if (z['im'] === 0 && this['im'] === 0) {
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return new Complex(this['re'] * z['re'], 0);
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}
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return new Complex(
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this['re'] * z['re'] - this['im'] * z['im'],
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this['re'] * z['im'] + this['im'] * z['re']);
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},
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/**
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* Divides two complex numbers
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*
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* @returns {Complex}
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*/
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'div': function (a, b) {
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const z = parse(a, b);
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const tInfin = this['isInfinite']();
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const zInfin = !(isFinite(z['re']) && isFinite(z['im']));
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const tIsZero = this['re'] === 0 && this['im'] === 0;
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const zIsZero = z['re'] === 0 && z['im'] === 0;
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// 0 / 0 = NaN and Infinity / Infinity = NaN
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if (tIsZero && zIsZero || tInfin && zInfin) {
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return Complex['NAN'];
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}
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// Infinity / 0 = Infinity
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if (zIsZero || tInfin) {
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return Complex['INFINITY'];
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}
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// 0 / Infinity = 0
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if (tIsZero || zInfin) {
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return Complex['ZERO'];
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}
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if (0 === z['im']) {
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// Divisor is real
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return new Complex(this['re'] / z['re'], this['im'] / z['re']);
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}
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if (Math.abs(z['re']) < Math.abs(z['im'])) {
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const x = z['re'] / z['im'];
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const t = z['re'] * x + z['im'];
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return new Complex(
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(this['re'] * x + this['im']) / t,
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(this['im'] * x - this['re']) / t);
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} else {
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const x = z['im'] / z['re'];
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const t = z['im'] * x + z['re'];
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return new Complex(
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(this['re'] + this['im'] * x) / t,
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(this['im'] - this['re'] * x) / t);
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}
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},
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/**
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* Calculate the power of two complex numbers
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*
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* @returns {Complex}
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*/
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'pow': function (a, b) {
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const z = parse(a, b);
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const tIsZero = this['re'] === 0 && this['im'] === 0;
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const zIsZero = z['re'] === 0 && z['im'] === 0;
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if (zIsZero) {
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return Complex['ONE'];
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}
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// If the exponent is real
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if (z['im'] === 0) {
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if (this['im'] === 0 && this['re'] > 0) {
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return new Complex(Math.pow(this['re'], z['re']), 0);
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} else if (this['re'] === 0) { // If base is fully imaginary
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switch ((z['re'] % 4 + 4) % 4) {
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case 0:
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return new Complex(Math.pow(this['im'], z['re']), 0);
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case 1:
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return new Complex(0, Math.pow(this['im'], z['re']));
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case 2:
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return new Complex(-Math.pow(this['im'], z['re']), 0);
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case 3:
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return new Complex(0, -Math.pow(this['im'], z['re']));
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}
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}
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}
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/* I couldn't find a good formula, so here is a derivation and optimization
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*
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* z_1^z_2 = (a + bi)^(c + di)
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* = exp((c + di) * log(a + bi)
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* = pow(a^2 + b^2, (c + di) / 2) * exp(i(c + di)atan2(b, a))
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* =>...
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* Re = (pow(a^2 + b^2, c / 2) * exp(-d * atan2(b, a))) * cos(d * log(a^2 + b^2) / 2 + c * atan2(b, a))
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* Im = (pow(a^2 + b^2, c / 2) * exp(-d * atan2(b, a))) * sin(d * log(a^2 + b^2) / 2 + c * atan2(b, a))
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*
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* =>...
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* Re = exp(c * log(sqrt(a^2 + b^2)) - d * atan2(b, a)) * cos(d * log(sqrt(a^2 + b^2)) + c * atan2(b, a))
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* Im = exp(c * log(sqrt(a^2 + b^2)) - d * atan2(b, a)) * sin(d * log(sqrt(a^2 + b^2)) + c * atan2(b, a))
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*
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* =>
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* Re = exp(c * logsq2 - d * arg(z_1)) * cos(d * logsq2 + c * arg(z_1))
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* Im = exp(c * logsq2 - d * arg(z_1)) * sin(d * logsq2 + c * arg(z_1))
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*
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*/
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if (tIsZero && z['re'] > 0) { // Same behavior as Wolframalpha, Zero if real part is zero
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return Complex['ZERO'];
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}
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const arg = Math.atan2(this['im'], this['re']);
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const loh = logHypot(this['re'], this['im']);
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let re = Math.exp(z['re'] * loh - z['im'] * arg);
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let im = z['im'] * loh + z['re'] * arg;
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return new Complex(
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re * Math.cos(im),
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re * Math.sin(im));
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},
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/**
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* Calculate the complex square root
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*
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* @returns {Complex}
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*/
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'sqrt': function () {
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const a = this['re'];
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const b = this['im'];
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if (b === 0) {
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// Real number case
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if (a >= 0) {
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return new Complex(Math.sqrt(a), 0);
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} else {
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return new Complex(0, Math.sqrt(-a));
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}
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}
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|
|
const r = hypot(a, b);
|
|
|
|
let re = Math.sqrt(0.5 * (r + Math.abs(a))); // sqrt(2x) / 2 = sqrt(x / 2)
|
|
let im = Math.abs(b) / (2 * re);
|
|
|
|
if (a >= 0) {
|
|
return new Complex(re, b < 0 ? -im : im);
|
|
} else {
|
|
return new Complex(im, b < 0 ? -re : re);
|
|
}
|
|
},
|
|
|
|
/**
|
|
* Calculate the complex exponent
|
|
*
|
|
* @returns {Complex}
|
|
*/
|
|
'exp': function () {
|
|
|
|
const er = Math.exp(this['re']);
|
|
|
|
if (this['im'] === 0) {
|
|
return new Complex(er, 0);
|
|
}
|
|
return new Complex(
|
|
er * Math.cos(this['im']),
|
|
er * Math.sin(this['im']));
|
|
},
|
|
|
|
/**
|
|
* Calculate the complex exponent and subtracts one.
|
|
*
|
|
* This may be more accurate than `Complex(x).exp().sub(1)` if
|
|
* `x` is small.
|
|
*
|
|
* @returns {Complex}
|
|
*/
|
|
'expm1': function () {
|
|
|
|
/**
|
|
* exp(a + i*b) - 1
|
|
= exp(a) * (cos(b) + j*sin(b)) - 1
|
|
= expm1(a)*cos(b) + cosm1(b) + j*exp(a)*sin(b)
|
|
*/
|
|
|
|
const a = this['re'];
|
|
const b = this['im'];
|
|
|
|
return new Complex(
|
|
Math.expm1(a) * Math.cos(b) + cosm1(b),
|
|
Math.exp(a) * Math.sin(b));
|
|
},
|
|
|
|
/**
|
|
* Calculate the natural log
|
|
*
|
|
* @returns {Complex}
|
|
*/
|
|
'log': function () {
|
|
|
|
const a = this['re'];
|
|
const b = this['im'];
|
|
|
|
if (b === 0 && a > 0) {
|
|
return new Complex(Math.log(a), 0);
|
|
}
|
|
|
|
return new Complex(
|
|
logHypot(a, b),
|
|
Math.atan2(b, a));
|
|
},
|
|
|
|
/**
|
|
* Calculate the magnitude of the complex number
|
|
*
|
|
* @returns {number}
|
|
*/
|
|
'abs': function () {
|
|
|
|
return hypot(this['re'], this['im']);
|
|
},
|
|
|
|
/**
|
|
* Calculate the angle of the complex number
|
|
*
|
|
* @returns {number}
|
|
*/
|
|
'arg': function () {
|
|
|
|
return Math.atan2(this['im'], this['re']);
|
|
},
|
|
|
|
/**
|
|
* Calculate the sine of the complex number
|
|
*
|
|
* @returns {Complex}
|
|
*/
|
|
'sin': function () {
|
|
|
|
// sin(z) = ( e^iz - e^-iz ) / 2i
|
|
// = sin(a)cosh(b) + i cos(a)sinh(b)
|
|
|
|
const a = this['re'];
|
|
const b = this['im'];
|
|
|
|
return new Complex(
|
|
Math.sin(a) * cosh(b),
|
|
Math.cos(a) * sinh(b));
|
|
},
|
|
|
|
/**
|
|
* Calculate the cosine
|
|
*
|
|
* @returns {Complex}
|
|
*/
|
|
'cos': function () {
|
|
|
|
// cos(z) = ( e^iz + e^-iz ) / 2
|
|
// = cos(a)cosh(b) - i sin(a)sinh(b)
|
|
|
|
const a = this['re'];
|
|
const b = this['im'];
|
|
|
|
return new Complex(
|
|
Math.cos(a) * cosh(b),
|
|
-Math.sin(a) * sinh(b));
|
|
},
|
|
|
|
/**
|
|
* Calculate the tangent
|
|
*
|
|
* @returns {Complex}
|
|
*/
|
|
'tan': function () {
|
|
|
|
// tan(z) = sin(z) / cos(z)
|
|
// = ( e^iz - e^-iz ) / ( i( e^iz + e^-iz ) )
|
|
// = ( e^2iz - 1 ) / i( e^2iz + 1 )
|
|
// = ( sin(2a) + i sinh(2b) ) / ( cos(2a) + cosh(2b) )
|
|
|
|
const a = 2 * this['re'];
|
|
const b = 2 * this['im'];
|
|
const d = Math.cos(a) + cosh(b);
|
|
|
|
return new Complex(
|
|
Math.sin(a) / d,
|
|
sinh(b) / d);
|
|
},
|
|
|
|
/**
|
|
* Calculate the cotangent
|
|
*
|
|
* @returns {Complex}
|
|
*/
|
|
'cot': function () {
|
|
|
|
// cot(c) = i(e^(ci) + e^(-ci)) / (e^(ci) - e^(-ci))
|
|
|
|
const a = 2 * this['re'];
|
|
const b = 2 * this['im'];
|
|
const d = Math.cos(a) - cosh(b);
|
|
|
|
return new Complex(
|
|
-Math.sin(a) / d,
|
|
sinh(b) / d);
|
|
},
|
|
|
|
/**
|
|
* Calculate the secant
|
|
*
|
|
* @returns {Complex}
|
|
*/
|
|
'sec': function () {
|
|
|
|
// sec(c) = 2 / (e^(ci) + e^(-ci))
|
|
|
|
const a = this['re'];
|
|
const b = this['im'];
|
|
const d = 0.5 * cosh(2 * b) + 0.5 * Math.cos(2 * a);
|
|
|
|
return new Complex(
|
|
Math.cos(a) * cosh(b) / d,
|
|
Math.sin(a) * sinh(b) / d);
|
|
},
|
|
|
|
/**
|
|
* Calculate the cosecans
|
|
*
|
|
* @returns {Complex}
|
|
*/
|
|
'csc': function () {
|
|
|
|
// csc(c) = 2i / (e^(ci) - e^(-ci))
|
|
|
|
const a = this['re'];
|
|
const b = this['im'];
|
|
const d = 0.5 * cosh(2 * b) - 0.5 * Math.cos(2 * a);
|
|
|
|
return new Complex(
|
|
Math.sin(a) * cosh(b) / d,
|
|
-Math.cos(a) * sinh(b) / d);
|
|
},
|
|
|
|
/**
|
|
* Calculate the complex arcus sinus
|
|
*
|
|
* @returns {Complex}
|
|
*/
|
|
'asin': function () {
|
|
|
|
// asin(c) = -i * log(ci + sqrt(1 - c^2))
|
|
|
|
const a = this['re'];
|
|
const b = this['im'];
|
|
|
|
const t1 = new Complex(
|
|
b * b - a * a + 1,
|
|
-2 * a * b)['sqrt']();
|
|
|
|
const t2 = new Complex(
|
|
t1['re'] - b,
|
|
t1['im'] + a)['log']();
|
|
|
|
return new Complex(t2['im'], -t2['re']);
|
|
},
|
|
|
|
/**
|
|
* Calculate the complex arcus cosinus
|
|
*
|
|
* @returns {Complex}
|
|
*/
|
|
'acos': function () {
|
|
|
|
// acos(c) = i * log(c - i * sqrt(1 - c^2))
|
|
|
|
const a = this['re'];
|
|
const b = this['im'];
|
|
|
|
const t1 = new Complex(
|
|
b * b - a * a + 1,
|
|
-2 * a * b)['sqrt']();
|
|
|
|
const t2 = new Complex(
|
|
t1['re'] - b,
|
|
t1['im'] + a)['log']();
|
|
|
|
return new Complex(Math.PI / 2 - t2['im'], t2['re']);
|
|
},
|
|
|
|
/**
|
|
* Calculate the complex arcus tangent
|
|
*
|
|
* @returns {Complex}
|
|
*/
|
|
'atan': function () {
|
|
|
|
// atan(c) = i / 2 log((i + x) / (i - x))
|
|
|
|
const a = this['re'];
|
|
const b = this['im'];
|
|
|
|
if (a === 0) {
|
|
|
|
if (b === 1) {
|
|
return new Complex(0, Infinity);
|
|
}
|
|
|
|
if (b === -1) {
|
|
return new Complex(0, -Infinity);
|
|
}
|
|
}
|
|
|
|
const d = a * a + (1.0 - b) * (1.0 - b);
|
|
|
|
const t1 = new Complex(
|
|
(1 - b * b - a * a) / d,
|
|
-2 * a / d).log();
|
|
|
|
return new Complex(-0.5 * t1['im'], 0.5 * t1['re']);
|
|
},
|
|
|
|
/**
|
|
* Calculate the complex arcus cotangent
|
|
*
|
|
* @returns {Complex}
|
|
*/
|
|
'acot': function () {
|
|
|
|
// acot(c) = i / 2 log((c - i) / (c + i))
|
|
|
|
const a = this['re'];
|
|
const b = this['im'];
|
|
|
|
if (b === 0) {
|
|
return new Complex(Math.atan2(1, a), 0);
|
|
}
|
|
|
|
const d = a * a + b * b;
|
|
return (d !== 0)
|
|
? new Complex(
|
|
a / d,
|
|
-b / d).atan()
|
|
: new Complex(
|
|
(a !== 0) ? a / 0 : 0,
|
|
(b !== 0) ? -b / 0 : 0).atan();
|
|
},
|
|
|
|
/**
|
|
* Calculate the complex arcus secant
|
|
*
|
|
* @returns {Complex}
|
|
*/
|
|
'asec': function () {
|
|
|
|
// asec(c) = -i * log(1 / c + sqrt(1 - i / c^2))
|
|
|
|
const a = this['re'];
|
|
const b = this['im'];
|
|
|
|
if (a === 0 && b === 0) {
|
|
return new Complex(0, Infinity);
|
|
}
|
|
|
|
const d = a * a + b * b;
|
|
return (d !== 0)
|
|
? new Complex(
|
|
a / d,
|
|
-b / d).acos()
|
|
: new Complex(
|
|
(a !== 0) ? a / 0 : 0,
|
|
(b !== 0) ? -b / 0 : 0).acos();
|
|
},
|
|
|
|
/**
|
|
* Calculate the complex arcus cosecans
|
|
*
|
|
* @returns {Complex}
|
|
*/
|
|
'acsc': function () {
|
|
|
|
// acsc(c) = -i * log(i / c + sqrt(1 - 1 / c^2))
|
|
|
|
const a = this['re'];
|
|
const b = this['im'];
|
|
|
|
if (a === 0 && b === 0) {
|
|
return new Complex(Math.PI / 2, Infinity);
|
|
}
|
|
|
|
const d = a * a + b * b;
|
|
return (d !== 0)
|
|
? new Complex(
|
|
a / d,
|
|
-b / d).asin()
|
|
: new Complex(
|
|
(a !== 0) ? a / 0 : 0,
|
|
(b !== 0) ? -b / 0 : 0).asin();
|
|
},
|
|
|
|
/**
|
|
* Calculate the complex sinh
|
|
*
|
|
* @returns {Complex}
|
|
*/
|
|
'sinh': function () {
|
|
|
|
// sinh(c) = (e^c - e^-c) / 2
|
|
|
|
const a = this['re'];
|
|
const b = this['im'];
|
|
|
|
return new Complex(
|
|
sinh(a) * Math.cos(b),
|
|
cosh(a) * Math.sin(b));
|
|
},
|
|
|
|
/**
|
|
* Calculate the complex cosh
|
|
*
|
|
* @returns {Complex}
|
|
*/
|
|
'cosh': function () {
|
|
|
|
// cosh(c) = (e^c + e^-c) / 2
|
|
|
|
const a = this['re'];
|
|
const b = this['im'];
|
|
|
|
return new Complex(
|
|
cosh(a) * Math.cos(b),
|
|
sinh(a) * Math.sin(b));
|
|
},
|
|
|
|
/**
|
|
* Calculate the complex tanh
|
|
*
|
|
* @returns {Complex}
|
|
*/
|
|
'tanh': function () {
|
|
|
|
// tanh(c) = (e^c - e^-c) / (e^c + e^-c)
|
|
|
|
const a = 2 * this['re'];
|
|
const b = 2 * this['im'];
|
|
const d = cosh(a) + Math.cos(b);
|
|
|
|
return new Complex(
|
|
sinh(a) / d,
|
|
Math.sin(b) / d);
|
|
},
|
|
|
|
/**
|
|
* Calculate the complex coth
|
|
*
|
|
* @returns {Complex}
|
|
*/
|
|
'coth': function () {
|
|
|
|
// coth(c) = (e^c + e^-c) / (e^c - e^-c)
|
|
|
|
const a = 2 * this['re'];
|
|
const b = 2 * this['im'];
|
|
const d = cosh(a) - Math.cos(b);
|
|
|
|
return new Complex(
|
|
sinh(a) / d,
|
|
-Math.sin(b) / d);
|
|
},
|
|
|
|
/**
|
|
* Calculate the complex coth
|
|
*
|
|
* @returns {Complex}
|
|
*/
|
|
'csch': function () {
|
|
|
|
// csch(c) = 2 / (e^c - e^-c)
|
|
|
|
const a = this['re'];
|
|
const b = this['im'];
|
|
const d = Math.cos(2 * b) - cosh(2 * a);
|
|
|
|
return new Complex(
|
|
-2 * sinh(a) * Math.cos(b) / d,
|
|
2 * cosh(a) * Math.sin(b) / d);
|
|
},
|
|
|
|
/**
|
|
* Calculate the complex sech
|
|
*
|
|
* @returns {Complex}
|
|
*/
|
|
'sech': function () {
|
|
|
|
// sech(c) = 2 / (e^c + e^-c)
|
|
|
|
const a = this['re'];
|
|
const b = this['im'];
|
|
const d = Math.cos(2 * b) + cosh(2 * a);
|
|
|
|
return new Complex(
|
|
2 * cosh(a) * Math.cos(b) / d,
|
|
-2 * sinh(a) * Math.sin(b) / d);
|
|
},
|
|
|
|
/**
|
|
* Calculate the complex asinh
|
|
*
|
|
* @returns {Complex}
|
|
*/
|
|
'asinh': function () {
|
|
|
|
// asinh(c) = log(c + sqrt(c^2 + 1))
|
|
|
|
let tmp = this['im'];
|
|
this['im'] = -this['re'];
|
|
this['re'] = tmp;
|
|
const res = this['asin']();
|
|
|
|
this['re'] = -this['im'];
|
|
this['im'] = tmp;
|
|
tmp = res['re'];
|
|
|
|
res['re'] = -res['im'];
|
|
res['im'] = tmp;
|
|
return res;
|
|
},
|
|
|
|
/**
|
|
* Calculate the complex acosh
|
|
*
|
|
* @returns {Complex}
|
|
*/
|
|
'acosh': function () {
|
|
|
|
// acosh(c) = log(c + sqrt(c^2 - 1))
|
|
|
|
const res = this['acos']();
|
|
if (res['im'] <= 0) {
|
|
const tmp = res['re'];
|
|
res['re'] = -res['im'];
|
|
res['im'] = tmp;
|
|
} else {
|
|
const tmp = res['im'];
|
|
res['im'] = -res['re'];
|
|
res['re'] = tmp;
|
|
}
|
|
return res;
|
|
},
|
|
|
|
/**
|
|
* Calculate the complex atanh
|
|
*
|
|
* @returns {Complex}
|
|
*/
|
|
'atanh': function () {
|
|
|
|
// atanh(c) = log((1+c) / (1-c)) / 2
|
|
|
|
const a = this['re'];
|
|
const b = this['im'];
|
|
|
|
const noIM = a > 1 && b === 0;
|
|
const oneMinus = 1 - a;
|
|
const onePlus = 1 + a;
|
|
const d = oneMinus * oneMinus + b * b;
|
|
|
|
const x = (d !== 0)
|
|
? new Complex(
|
|
(onePlus * oneMinus - b * b) / d,
|
|
(b * oneMinus + onePlus * b) / d)
|
|
: new Complex(
|
|
(a !== -1) ? (a / 0) : 0,
|
|
(b !== 0) ? (b / 0) : 0);
|
|
|
|
const temp = x['re'];
|
|
x['re'] = logHypot(x['re'], x['im']) / 2;
|
|
x['im'] = Math.atan2(x['im'], temp) / 2;
|
|
if (noIM) {
|
|
x['im'] = -x['im'];
|
|
}
|
|
return x;
|
|
},
|
|
|
|
/**
|
|
* Calculate the complex acoth
|
|
*
|
|
* @returns {Complex}
|
|
*/
|
|
'acoth': function () {
|
|
|
|
// acoth(c) = log((c+1) / (c-1)) / 2
|
|
|
|
const a = this['re'];
|
|
const b = this['im'];
|
|
|
|
if (a === 0 && b === 0) {
|
|
return new Complex(0, Math.PI / 2);
|
|
}
|
|
|
|
const d = a * a + b * b;
|
|
return (d !== 0)
|
|
? new Complex(
|
|
a / d,
|
|
-b / d).atanh()
|
|
: new Complex(
|
|
(a !== 0) ? a / 0 : 0,
|
|
(b !== 0) ? -b / 0 : 0).atanh();
|
|
},
|
|
|
|
/**
|
|
* Calculate the complex acsch
|
|
*
|
|
* @returns {Complex}
|
|
*/
|
|
'acsch': function () {
|
|
|
|
// acsch(c) = log((1+sqrt(1+c^2))/c)
|
|
|
|
const a = this['re'];
|
|
const b = this['im'];
|
|
|
|
if (b === 0) {
|
|
|
|
return new Complex(
|
|
(a !== 0)
|
|
? Math.log(a + Math.sqrt(a * a + 1))
|
|
: Infinity, 0);
|
|
}
|
|
|
|
const d = a * a + b * b;
|
|
return (d !== 0)
|
|
? new Complex(
|
|
a / d,
|
|
-b / d).asinh()
|
|
: new Complex(
|
|
(a !== 0) ? a / 0 : 0,
|
|
(b !== 0) ? -b / 0 : 0).asinh();
|
|
},
|
|
|
|
/**
|
|
* Calculate the complex asech
|
|
*
|
|
* @returns {Complex}
|
|
*/
|
|
'asech': function () {
|
|
|
|
// asech(c) = log((1+sqrt(1-c^2))/c)
|
|
|
|
const a = this['re'];
|
|
const b = this['im'];
|
|
|
|
if (this['isZero']()) {
|
|
return Complex['INFINITY'];
|
|
}
|
|
|
|
const d = a * a + b * b;
|
|
return (d !== 0)
|
|
? new Complex(
|
|
a / d,
|
|
-b / d).acosh()
|
|
: new Complex(
|
|
(a !== 0) ? a / 0 : 0,
|
|
(b !== 0) ? -b / 0 : 0).acosh();
|
|
},
|
|
|
|
/**
|
|
* Calculate the complex inverse 1/z
|
|
*
|
|
* @returns {Complex}
|
|
*/
|
|
'inverse': function () {
|
|
|
|
// 1 / 0 = Infinity and 1 / Infinity = 0
|
|
if (this['isZero']()) {
|
|
return Complex['INFINITY'];
|
|
}
|
|
|
|
if (this['isInfinite']()) {
|
|
return Complex['ZERO'];
|
|
}
|
|
|
|
const a = this['re'];
|
|
const b = this['im'];
|
|
|
|
const d = a * a + b * b;
|
|
|
|
return new Complex(a / d, -b / d);
|
|
},
|
|
|
|
/**
|
|
* Returns the complex conjugate
|
|
*
|
|
* @returns {Complex}
|
|
*/
|
|
'conjugate': function () {
|
|
|
|
return new Complex(this['re'], -this['im']);
|
|
},
|
|
|
|
/**
|
|
* Gets the negated complex number
|
|
*
|
|
* @returns {Complex}
|
|
*/
|
|
'neg': function () {
|
|
|
|
return new Complex(-this['re'], -this['im']);
|
|
},
|
|
|
|
/**
|
|
* Ceils the actual complex number
|
|
*
|
|
* @returns {Complex}
|
|
*/
|
|
'ceil': function (places) {
|
|
|
|
places = Math.pow(10, places || 0);
|
|
|
|
return new Complex(
|
|
Math.ceil(this['re'] * places) / places,
|
|
Math.ceil(this['im'] * places) / places);
|
|
},
|
|
|
|
/**
|
|
* Floors the actual complex number
|
|
*
|
|
* @returns {Complex}
|
|
*/
|
|
'floor': function (places) {
|
|
|
|
places = Math.pow(10, places || 0);
|
|
|
|
return new Complex(
|
|
Math.floor(this['re'] * places) / places,
|
|
Math.floor(this['im'] * places) / places);
|
|
},
|
|
|
|
/**
|
|
* Ceils the actual complex number
|
|
*
|
|
* @returns {Complex}
|
|
*/
|
|
'round': function (places) {
|
|
|
|
places = Math.pow(10, places || 0);
|
|
|
|
return new Complex(
|
|
Math.round(this['re'] * places) / places,
|
|
Math.round(this['im'] * places) / places);
|
|
},
|
|
|
|
/**
|
|
* Compares two complex numbers
|
|
*
|
|
* **Note:** new Complex(Infinity).equals(Infinity) === false
|
|
*
|
|
* @returns {boolean}
|
|
*/
|
|
'equals': function (a, b) {
|
|
|
|
const z = parse(a, b);
|
|
|
|
return Math.abs(z['re'] - this['re']) <= Complex['EPSILON'] &&
|
|
Math.abs(z['im'] - this['im']) <= Complex['EPSILON'];
|
|
},
|
|
|
|
/**
|
|
* Clones the actual object
|
|
*
|
|
* @returns {Complex}
|
|
*/
|
|
'clone': function () {
|
|
|
|
return new Complex(this['re'], this['im']);
|
|
},
|
|
|
|
/**
|
|
* Gets a string of the actual complex number
|
|
*
|
|
* @returns {string}
|
|
*/
|
|
'toString': function () {
|
|
|
|
let a = this['re'];
|
|
let b = this['im'];
|
|
let ret = "";
|
|
|
|
if (this['isNaN']()) {
|
|
return 'NaN';
|
|
}
|
|
|
|
if (this['isInfinite']()) {
|
|
return 'Infinity';
|
|
}
|
|
|
|
if (Math.abs(a) < Complex['EPSILON']) {
|
|
a = 0;
|
|
}
|
|
|
|
if (Math.abs(b) < Complex['EPSILON']) {
|
|
b = 0;
|
|
}
|
|
|
|
// If is real number
|
|
if (b === 0) {
|
|
return ret + a;
|
|
}
|
|
|
|
if (a !== 0) {
|
|
ret += a;
|
|
ret += " ";
|
|
if (b < 0) {
|
|
b = -b;
|
|
ret += "-";
|
|
} else {
|
|
ret += "+";
|
|
}
|
|
ret += " ";
|
|
} else if (b < 0) {
|
|
b = -b;
|
|
ret += "-";
|
|
}
|
|
|
|
if (1 !== b) { // b is the absolute imaginary part
|
|
ret += b;
|
|
}
|
|
return ret + "i";
|
|
},
|
|
|
|
/**
|
|
* Returns the actual number as a vector
|
|
*
|
|
* @returns {Array}
|
|
*/
|
|
'toVector': function () {
|
|
|
|
return [this['re'], this['im']];
|
|
},
|
|
|
|
/**
|
|
* Returns the actual real value of the current object
|
|
*
|
|
* @returns {number|null}
|
|
*/
|
|
'valueOf': function () {
|
|
|
|
if (this['im'] === 0) {
|
|
return this['re'];
|
|
}
|
|
return null;
|
|
},
|
|
|
|
/**
|
|
* Determines whether a complex number is not on the Riemann sphere.
|
|
*
|
|
* @returns {boolean}
|
|
*/
|
|
'isNaN': function () {
|
|
return isNaN(this['re']) || isNaN(this['im']);
|
|
},
|
|
|
|
/**
|
|
* Determines whether or not a complex number is at the zero pole of the
|
|
* Riemann sphere.
|
|
*
|
|
* @returns {boolean}
|
|
*/
|
|
'isZero': function () {
|
|
return this['im'] === 0 && this['re'] === 0;
|
|
},
|
|
|
|
/**
|
|
* Determines whether a complex number is not at the infinity pole of the
|
|
* Riemann sphere.
|
|
*
|
|
* @returns {boolean}
|
|
*/
|
|
'isFinite': function () {
|
|
return isFinite(this['re']) && isFinite(this['im']);
|
|
},
|
|
|
|
/**
|
|
* Determines whether or not a complex number is at the infinity pole of the
|
|
* Riemann sphere.
|
|
*
|
|
* @returns {boolean}
|
|
*/
|
|
'isInfinite': function () {
|
|
return !this['isFinite']();
|
|
}
|
|
};
|
|
|
|
Complex['ZERO'] = new Complex(0, 0);
|
|
Complex['ONE'] = new Complex(1, 0);
|
|
Complex['I'] = new Complex(0, 1);
|
|
Complex['PI'] = new Complex(Math.PI, 0);
|
|
Complex['E'] = new Complex(Math.E, 0);
|
|
Complex['INFINITY'] = new Complex(Infinity, Infinity);
|
|
Complex['NAN'] = new Complex(NaN, NaN);
|
|
Complex['EPSILON'] = 1e-15;
|
|
export {
|
|
Complex as default, Complex
|
|
};
|