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326 lines
12 KiB
JavaScript
326 lines
12 KiB
JavaScript
/*
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author: Christian Bender
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license: MIT-license
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The namespace LinearAlgebra contains useful classes and functions for dealing with
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linear algebra under JavaScript.
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*/
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var LinearAlgebra;
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(function (LinearAlgebra) {
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/*
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class: Vector
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This class represents a vector of arbitrary size and operations on it.
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*/
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var Vector = /** @class */ (function () {
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// constructor
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function Vector(N, comps) {
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if (comps === void 0) { comps = []; }
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this.components = new Array(N);
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if (comps.length == 0) {
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for (var i = 0; i < N; i++) {
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this.components[i] = 0.0;
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}
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}
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else {
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if (N == comps.length) {
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this.components = comps;
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}
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else {
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throw "Vector: invalide size!";
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}
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}
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} // end of constructor
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// returns the size of this vector.
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// not the eulidean length!
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Vector.prototype.size = function () {
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return this.components.length;
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};
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// computes the eulidean length.
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Vector.prototype.eulideanLength = function () {
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var sum = 0;
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for (var i = 0; i < this.components.length; i++) {
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sum += this.components[i] * this.components[i];
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}
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return Math.sqrt(sum);
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};
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// getter for the components of the vector.
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// returns a specified component (index)
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Vector.prototype.component = function (index) {
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return this.components[index];
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};
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// setter for a specified component of this vector.
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Vector.prototype.changeComponent = function (index, value) {
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if (index >= 0 && index < this.components.length) {
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this.components[index] = value;
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}
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else {
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throw "changeComponent: index out of bounds!";
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}
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};
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// vector addition
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Vector.prototype.add = function (other) {
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if (this.size() == other.size()) {
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var SIZE = this.size();
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var ans = new Vector(SIZE);
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for (var i = 0; i < SIZE; i++) {
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ans.changeComponent(i, (this.components[i] + other.component(i)));
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}
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return ans;
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}
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else {
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throw "add: vector must have same size!";
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}
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};
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// vector subtraction
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Vector.prototype.sub = function (other) {
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if (this.size() == other.size()) {
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var SIZE = this.size();
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var ans = new Vector(SIZE);
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for (var i = 0; i < SIZE; i++) {
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ans.changeComponent(i, (this.components[i] - other.component(i)));
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}
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return ans;
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}
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else {
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throw "add: vector must have same size!";
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}
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};
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// dot-product
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Vector.prototype.dot = function (other) {
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var sum = 0;
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if (other.size() == this.size()) {
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var SIZE = other.size();
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for (var i = 0; i < SIZE; i++) {
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sum += this.components[i] * other.component(i);
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}
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return sum;
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}
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else {
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throw "dot: vectors must have same size!";
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}
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};
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// scalar multiplication
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Vector.prototype.scalar = function (s) {
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var SIZE = this.size();
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var ans = new Vector(SIZE);
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for (var i = 0; i < SIZE; i++) {
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ans.changeComponent(i, (this.components[i] * s));
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}
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return ans;
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};
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// returns a string representation of this vector.
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Vector.prototype.toString = function () {
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var ans = "(";
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var SIZE = this.components.length;
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for (var i = 0; i < SIZE; i++) {
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if (i < SIZE - 1) {
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ans += this.components[i] + ",";
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}
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else {
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ans += this.components[i] + ")";
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}
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}
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return ans;
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};
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// converts this vector in a unit basis vector and returns it.
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// the One is on position 'pos'
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Vector.prototype.createUnitBasis = function (pos) {
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if (pos >= 0 && pos < this.components.length) {
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for (var i = 0; i < this.components.length; i++) {
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if (i == pos) {
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this.components[i] = 1.0;
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}
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else {
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this.components[i] = 0.0;
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}
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}
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}
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else {
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throw "createUnitBasis: index out of bounds";
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}
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return this;
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};
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// normalizes this vector and returns it.
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Vector.prototype.norm = function () {
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var SIZE = this.size();
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var quotient = 1.0 / this.eulideanLength();
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for (var i = 0; i < SIZE; i++) {
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this.components[i] = this.components[i] * quotient;
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}
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return this;
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};
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// returns true if the vectors are equal otherwise false.
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Vector.prototype.equal = function (other) {
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var ans = true;
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var SIZE = this.size();
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var EPSILON = 0.001;
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if (SIZE == other.size()) {
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for (var i = 0; i < SIZE; i++) {
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if (Math.abs(this.components[i] - other.component(i)) > EPSILON) {
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ans = false;
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}
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}
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}
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else {
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ans = false;
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}
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return ans;
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};
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return Vector;
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}()); // end of class Vector
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LinearAlgebra.Vector = Vector;
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// -------------- global functions ---------------------------------
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// returns a unit basis vector of size N with a One on position 'pos'
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function unitBasisVector(N, pos) {
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var ans = new Vector(N);
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for (var i = 0; i < N; i++) {
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if (i == pos) {
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ans.changeComponent(i, 1.0);
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}
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else {
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ans.changeComponent(i, 0);
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}
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}
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return ans;
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}
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LinearAlgebra.unitBasisVector = unitBasisVector;
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// returns a random vector with integer components (between 'a' and 'b') of size N.
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function randomVectorInt(N, a, b) {
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var ans = new Vector(N);
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for (var i = 0; i < N; i++) {
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ans.changeComponent(i, (Math.floor((Math.random() * b) + a)));
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}
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return ans;
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}
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LinearAlgebra.randomVectorInt = randomVectorInt;
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// returns a random vector with floating point components (between 'a' and 'b') of size N.
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function randomVectorFloat(N, a, b) {
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var ans = new Vector(N);
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for (var i = 0; i < N; i++) {
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ans.changeComponent(i, ((Math.random() * b) + a));
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}
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return ans;
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}
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LinearAlgebra.randomVectorFloat = randomVectorFloat;
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// ------------------ end of global functions -----------------------------
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/*
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class: Matrix
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This class represents a matrix of arbitrary size and operations on it.
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*/
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var Matrix = /** @class */ (function () {
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// constructor for zero-matrix or fix number matrix.
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function Matrix(row, col, comps) {
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if (comps === void 0) { comps = []; }
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if (comps.length == 0) {
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this.matrix = new Array();
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var rowVector = new Array();
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for (var i = 0; i < row; i++) {
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for (var j = 0; j < col; j++) {
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rowVector[j] = 0;
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}
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this.matrix[i] = rowVector;
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rowVector = new Array();
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}
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}
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else {
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this.matrix = comps;
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}
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this.rows = row;
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this.cols = col;
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}
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// returns the specified component.
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Matrix.prototype.component = function (x, y) {
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if (x >= 0 && x < this.rows && y >= 0 && y < this.cols) {
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return this.matrix[x][y];
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}
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else {
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throw new Error("component: index out of bounds");
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}
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};
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// changes the specified component with value 'value'.
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Matrix.prototype.changeComponent = function (x, y, value) {
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if (x >= 0 && x < this.rows && y >= 0 && y < this.cols) {
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this.matrix[x][y] = value;
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}
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else {
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throw new Error("changeComponent: index out of bounds");
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}
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};
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// returns a string representation of this matrix.
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Matrix.prototype.toString = function () {
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var ans = "";
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for (var i = 0; i < this.rows; i++) {
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ans += "|";
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for (var j = 0; j < this.cols; j++) {
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if (j < this.cols - 1) {
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ans += this.matrix[i][j] + ",";
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}
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else {
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if (i < this.rows - 1) {
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ans += this.matrix[i][j] + "|\n";
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}
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else {
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ans += this.matrix[i][j] + "|";
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}
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}
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}
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}
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return ans;
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};
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// returns the dimension rows x cols as number array
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Matrix.prototype.dimension = function () {
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var ans = new Array();
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ans[0] = this.rows;
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ans[1] = this.cols;
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return ans;
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};
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// matrix addition. returns the result.
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Matrix.prototype.add = function (other) {
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if (this.rows == other.dimension()[0]
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&& this.cols == other.dimension()[1]) {
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var ans = new Matrix(this.rows, this.cols);
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for (var i = 0; i < this.rows; i++) {
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for (var j = 0; j < this.cols; j++) {
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ans.changeComponent(i, j, (this.matrix[i][j] + other.component(i, j)));
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}
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}
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return ans;
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}
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else {
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throw new Error("add: matrices must have same dimension!");
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}
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};
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// returns true if the matrices are equal, otherwise false.
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Matrix.prototype.equal = function (other) {
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var ans = true;
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var EPSILON = 0.001;
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if (this.rows == other.dimension()[0]
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&& this.cols == other.dimension()[1]) {
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for (var i = 0; i < this.rows; i++) {
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for (var j = 0; j < this.cols; j++) {
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if (Math.abs(this.matrix[i][j] - other.component(i, j)) > EPSILON) {
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ans = false;
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}
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}
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}
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}
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else {
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ans = false;
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}
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return ans;
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};
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// matrix-scalar multiplication
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Matrix.prototype.scalar = function (c) {
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var ans = new Matrix(this.rows, this.cols);
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for (var i = 0; i < this.rows; i++) {
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for (var j = 0; j < this.cols; j++) {
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ans.changeComponent(i, j, (this.matrix[i][j] * c));
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}
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}
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return ans;
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};
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return Matrix;
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}()); // end of class Matrix
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LinearAlgebra.Matrix = Matrix;
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})(LinearAlgebra || (LinearAlgebra = {})); // end of namespace LinearAlgebra
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