dsp-collection/math/Complex.js

A collection of JavaScript modules for digital signal processing (written in TypeScript)

import * as MathUtils from "./MathUtils.js";
class Complex {
    constructor(re, im = 0) {
        this.re = re;
        this.im = im;
    }
    toString() {
        return "(" + this.re + ", " + this.im + ")";
    }
    toNumber(eps) {
        const absIm = Math.abs(this.im);
        if (!(absIm <= eps || absIm <= Math.abs(this.re) * eps)) {
            throw new Error("The imaginary part of the complex number is not neglectable small for the conversion to a real number. re=" + this.re + " im=" + this.im + " eps=" + eps + ".");
        }
        return this.re;
    }
    isNaN() {
        return isNaN(this.re) || isNaN(this.im);
    }
    isInfinite() {
        return this.re == Infinity || this.re == -Infinity || this.im == Infinity || this.im == -Infinity;
    }
    isFinite() {
        return isFinite(this.re) && isFinite(this.im);
    }
    equals(x) {
        return x && this.re == x.re && this.im == x.im;
    }
    fuzzyEquals(x, eps) {
        return MathUtils.fuzzyEquals(this.re, x.re, eps) && MathUtils.fuzzyEquals(this.im, x.im, eps);
    }
    static expj(arg) {
        return new Complex(Math.cos(arg), Math.sin(arg));
    }
    static fromPolar(abs, arg) {
        return new Complex(abs * Math.cos(arg), abs * Math.sin(arg));
    }
    abs() {
        return Math.hypot(this.re, this.im);
    }
    arg() {
        return Math.atan2(this.im, this.re);
    }
    conj() {
        return new Complex(this.re, -this.im);
    }
    neg() {
        return new Complex(-this.re, -this.im);
    }
    reciprocal() {
        if (this.isNaN()) {
            return Complex.NaN;
        }
        if (this.isInfinite()) {
            return Complex.ZERO;
        }
        const scale = this.re * this.re + this.im * this.im;
        if (scale == 0) {
            return Complex.INFINITY;
        }
        return new Complex(this.re / scale, -this.im / scale);
    }
    exp() {
        return Complex.fromPolar(Math.exp(this.re), this.im);
    }
    log() {
        return new Complex(Math.log(this.abs()), this.arg());
    }
    sqr() {
        return new Complex(this.re * this.re - this.im * this.im, 2 * this.re * this.im);
    }
    sqrt() {
        if (this.re == 0 && this.im == 0) {
            return Complex.ZERO;
        }
        const m = this.abs();
        return new Complex(Math.sqrt((m + this.re) / 2), Math.sign(this.im) * Math.sqrt((m - this.re) / 2));
    }
    addReal(x) {
        return new Complex(this.re + x, this.im);
    }
    add(x) {
        return new Complex(this.re + x.re, this.im + x.im);
    }
    subReal(x) {
        return new Complex(this.re - x, this.im);
    }
    static subFromReal(x, y) {
        return new Complex(x - y.re, -y.im);
    }
    sub(x) {
        return new Complex(this.re - x.re, this.im - x.im);
    }
    mulReal(x) {
        return new Complex(this.re * x, this.im * x);
    }
    mul(x) {
        return new Complex(this.re * x.re - this.im * x.im, this.re * x.im + this.im * x.re);
    }
    divReal(x) {
        return new Complex(this.re / x, this.im / x);
    }
    div(x) {
        const m = x.re * x.re + x.im * x.im;
        return new Complex((this.re * x.re + this.im * x.im) / m, (this.im * x.re - this.re * x.im) / m);
    }
    static divFromReal(x, y) {
        const m = y.re * y.re + y.im * y.im;
        return new Complex(x * y.re / m, -x * y.im / m);
    }
    powInt(x) {
        if (!Number.isInteger(x)) {
            throw new Error("powInt() used with non-integer exponent.");
        }
        return Complex.fromPolar(Math.pow(this.abs(), x), this.arg() * x);
    }
    powReal(x) {
        return this.log().mulReal(x).exp();
    }
    pow(x) {
        return this.log().mul(x).exp();
    }
}
Complex.I = new Complex(0, 1);
Complex.ZERO = new Complex(0);
Complex.ONE = new Complex(1);
Complex.TWO = new Complex(2);
Complex.NaN = new Complex(NaN, NaN);
Complex.INFINITY = new Complex(Infinity, Infinity);
export default Complex;
//# sourceMappingURL=Complex.js.map