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diff --git a/euler-golf/js/cx.js b/euler-golf/js/cx.js
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+// http://www.russellcottrell.com/fractalsEtc/cx.js
+
+class cx {
+ static degrees(d) {
+ cx._RD = d ? Math.PI / 180 : 1;
+ }
+ // Math.PI/180 for degrees, 1 for radians
+ // applies to i/o (constructor, get/set arg, and toString etc.)
+
+ constructor(x, y, polar) {
+ if (!polar) {
+ this.re = x;
+ this.im = y;
+ } else {
+ y *= cx._RD; // may be radians or degrees
+ this.re = x * Math.cos(y);
+ this.im = x * Math.sin(y);
+ }
+ }
+
+ get abs() {
+ return Math.sqrt(this.re * this.re + this.im * this.im);
+ }
+
+ set abs(r) {
+ var theta = this._arg;
+ this.re = r * Math.cos(theta);
+ this.im = r * Math.sin(theta);
+ }
+
+ get arg() {
+ // returns radians or degrees, non-negative
+ return (
+ ((Math.atan2(this.im, this.re) + 2 * Math.PI) % (2 * Math.PI)) / cx._RD
+ );
+ }
+
+ set arg(theta) {
+ // may be radians or degrees
+ var r = this.abs;
+ this.re = r * Math.cos(theta * cx._RD);
+ this.im = r * Math.sin(theta * cx._RD);
+ }
+
+ get _arg() {
+ // internal; returns radians
+ return Math.atan2(this.im, this.re);
+ }
+
+ static get i() {
+ return new cx(0, 1);
+ }
+
+ static set i(x) {
+ throw new Error("i is read-only");
+ }
+
+ toString(polar) {
+ if (!polar)
+ return (
+ this.re.toString() +
+ (this.im >= 0 ? " + " : " - ") +
+ Math.abs(this.im).toString() +
+ "i"
+ );
+ else return this.abs.toString() + " cis " + this.arg.toString();
+ }
+
+ toPrecision(n, polar) {
+ if (!polar)
+ return (
+ this.re.toPrecision(n) +
+ (this.im >= 0 ? " + " : " - ") +
+ Math.abs(this.im).toPrecision(n) +
+ "i"
+ );
+ else return this.abs.toPrecision(n) + " cis " + this.arg.toPrecision(n);
+ }
+
+ toPrecis(n, polar) {
+ // trims trailing zeros
+ if (!polar)
+ return (
+ parseFloat(this.re.toPrecision(n)).toString() +
+ (this.im >= 0 ? " + " : " - ") +
+ parseFloat(Math.abs(this.im).toPrecision(n)).toString() +
+ "i"
+ );
+ else
+ return (
+ parseFloat(this.abs.toPrecision(n)).toString() +
+ " cis " +
+ parseFloat(this.arg.toPrecision(n)).toString()
+ );
+ }
+
+ toFixed(n, polar) {
+ if (!polar)
+ return (
+ this.re.toFixed(n) +
+ (this.im >= 0 ? " + " : " - ") +
+ Math.abs(this.im).toFixed(n) +
+ "i"
+ );
+ else return this.abs.toFixed(n) + " cis " + this.arg.toFixed(n);
+ }
+
+ toExponential(n, polar) {
+ if (!polar)
+ return (
+ this.re.toExponential(n) +
+ (this.im >= 0 ? " + " : " - ") +
+ Math.abs(this.im).toExponential(n) +
+ "i"
+ );
+ else return this.abs.toExponential(n) + " cis " + this.arg.toExponential(n);
+ }
+
+ static getReals(c, d) {
+ // when c or d may be simple or complex
+ var x, y, u, v;
+ if (c instanceof cx) {
+ x = c.re;
+ y = c.im;
+ } else {
+ x = c;
+ y = 0;
+ }
+ if (d instanceof cx) {
+ u = d.re;
+ v = d.im;
+ } else {
+ u = d;
+ v = 0;
+ }
+ return [x, y, u, v];
+ }
+
+ static conj(c) {
+ return new cx(c.re, -c.im);
+ }
+
+ static neg(c) {
+ return new cx(-c.re, -c.im);
+ }
+
+ static add(c, d) {
+ var a = cx.getReals(c, d);
+ var x = a[0];
+ var y = a[1];
+ var u = a[2];
+ var v = a[3];
+ return new cx(x + u, y + v);
+ }
+
+ static sub(c, d) {
+ var a = cx.getReals(c, d);
+ var x = a[0];
+ var y = a[1];
+ var u = a[2];
+ var v = a[3];
+ return new cx(x - u, y - v);
+ }
+
+ static mult(c, d) {
+ var a = cx.getReals(c, d);
+ var x = a[0];
+ var y = a[1];
+ var u = a[2];
+ var v = a[3];
+ return new cx(x * u - y * v, x * v + y * u);
+ }
+
+ static div(c, d) {
+ var a = cx.getReals(c, d);
+ var x = a[0];
+ var y = a[1];
+ var u = a[2];
+ var v = a[3];
+ return new cx(
+ (x * u + y * v) / (u * u + v * v),
+ (y * u - x * v) / (u * u + v * v)
+ );
+ }
+
+ static pow(c, int) {
+ if (Number.isInteger(int) && int >= 0) {
+ var r = Math.pow(c.abs, int);
+ var theta = int * c._arg;
+ return new cx(r * Math.cos(theta), r * Math.sin(theta));
+ } else return NaN;
+ }
+
+ static root(c, int, k) {
+ if (!k) k = 0;
+ if (
+ Number.isInteger(int) &&
+ int >= 2 &&
+ Number.isInteger(k) &&
+ k >= 0 &&
+ k < int
+ ) {
+ var r = Math.pow(c.abs, 1 / int);
+ var theta = (c._arg + 2 * k * Math.PI) / int;
+ return new cx(r * Math.cos(theta), r * Math.sin(theta));
+ } else return NaN;
+ }
+
+ static log(c) {
+ return new cx(Math.log(c.abs), c._arg);
+ }
+
+ static exp(c) {
+ var r = Math.exp(c.re);
+ var theta = c.im;
+ return new cx(r * Math.cos(theta), r * Math.sin(theta));
+ }
+
+ static sin(c) {
+ var a = c.re;
+ var b = c.im;
+ return new cx(Math.sin(a) * Math.cosh(b), Math.cos(a) * Math.sinh(b));
+ }
+
+ static cos(c) {
+ var a = c.re;
+ var b = c.im;
+ return new cx(Math.cos(a) * Math.cosh(b), -Math.sin(a) * Math.sinh(b));
+ }
+
+ static tan(c) {
+ return cx.div(cx.sin(c), cx.cos(c));
+ }
+
+ static asin(c, k) {
+ if (!k) k = 0;
+ var ic = cx.mult(cx.i, c);
+ var c2 = cx.pow(c, 2);
+ return cx.mult(
+ cx.neg(cx.i),
+ cx.log(cx.add(ic, cx.root(cx.sub(1, c2), 2, k)))
+ );
+ }
+
+ static acos(c, k) {
+ if (!k) k = 0;
+ var c2 = cx.pow(c, 2);
+ return cx.mult(
+ cx.neg(cx.i),
+ cx.log(cx.add(c, cx.mult(cx.i, cx.root(cx.sub(1, c2), 2, k))))
+ );
+ }
+
+ static atan(c) {
+ return cx.mult(
+ cx.div(cx.i, 2),
+ cx.log(cx.div(cx.add(cx.i, c), cx.sub(cx.i, c)))
+ );
+ }
+
+ static sinh(c) {
+ var a = c.re;
+ var b = c.im;
+ return new cx(Math.sinh(a) * Math.cos(b), Math.cosh(a) * Math.sin(b));
+ }
+
+ static cosh(c) {
+ var a = c.re;
+ var b = c.im;
+ return new cx(Math.cosh(a) * Math.cos(b), Math.sinh(a) * Math.sin(b));
+ }
+
+ static tanh(c) {
+ return cx.div(cx.sinh(c), cx.cosh(c));
+ }
+
+ static asinh(c, k) {
+ if (!k) k = 0;
+ var c2 = cx.pow(c, 2);
+ return cx.log(cx.add(c, cx.root(cx.add(c2, 1), 2, k)));
+ }
+
+ static acosh(c, k) {
+ if (!k) k = 0;
+ var c2 = cx.pow(c, 2);
+ return cx.log(cx.add(c, cx.root(cx.sub(c2, 1), 2, k)));
+ }
+
+ static atanh(c) {
+ return cx.mult(cx.div(1, 2), cx.log(cx.div(cx.add(1, c), cx.sub(1, c))));
+ }
+
+ static copy(c) {
+ return new cx(c.re, c.im);
+ }
+
+ static eq(c, d, epsilon) {
+ if (!epsilon) {
+ if (c.re == d.re && c.im == d.im) return true;
+ } else {
+ if (Math.abs(c.re - d.re) < epsilon && Math.abs(c.im - d.im) < epsilon)
+ return true;
+ }
+ return false;
+ }
+}
+
+cx.degrees(true); // need to call this