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stropitekstropitek
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feat: add method subMatrixView
1 parent f077732 commit aa1df18

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Lines changed: 131 additions & 0 deletions

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‎src/abstractMatrix.js‎

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@@ -6,6 +6,7 @@ var arrayUtils = require('ml-array-utils');
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var util = require('./util');
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var MatrixTransposeView = require('./views/transpose');
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var MatrixRowView = require('./views/row');
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var MatrixSubView = require('./views/sub');
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function abstractMatrix(superCtor) {
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if (superCtor === undefined) superCtor = Object;
@@ -1182,6 +1183,10 @@ function abstractMatrix(superCtor) {
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util.checkRowIndex(this, row);
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return new MatrixRowView(this, row);
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}
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subMatrixView(rowIndices, columnIndices, startColumn, endColumn) {
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return new MatrixSubView(this, rowIndices, columnIndices, startColumn, endColumn);
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}
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}
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Matrix.prototype.klass = 'Matrix';

‎src/util.js‎

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@@ -63,3 +63,48 @@ exports.checkColumnVector = function checkColumnVector(matrix, vector) {
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}
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return vector;
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};
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exports.checkIndices = function checkIndices(matrix, rowIndices, columnIndices) {
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var rowOut = rowIndices.some(r => {
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return r < 0 || r >= matrix.rows;
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});
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var columnOut = columnIndices.some(c => {
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return c < 0 || c >= matrix.columns;
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});
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if (rowOut || columnOut) {
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throw new RangeError('Indices are out of range')
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}
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if (typeof rowIndices !== 'object' || typeof columnIndices !== 'object') {
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throw new TypeError('Unexpected type for row/column indices');
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}
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if (!Array.isArray(rowIndices)) rowIndices = Array.from(rowIndices);
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if (!Array.isArray(columnIndices)) rowIndices = Array.from(columnIndices);
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return {
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row: rowIndices,
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column: columnIndices
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};
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};
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exports.checkRange = function checkRange(matrix, startRow, endRow, startColumn, endColumn) {
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if (arguments.length !== 5) throw new TypeError('Invalid argument type');
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var notAllNumbers = Array.from(arguments).slice(1).some(function (arg) {
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return typeof arg !== 'number';
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});
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if (notAllNumbers) throw new TypeError('Invalid argument type');
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if (startRow > endRow || startColumn > endColumn || startRow < 0 || startRow >= matrix.rows || endRow < 0 || endRow >= matrix.rows || startColumn < 0 || startColumn >= matrix.columns || endColumn < 0 || endColumn >= matrix.columns) {
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throw new RangeError('Submatrix indices are out of range');
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}
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};
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exports.getRange = function getRange(from, to) {
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var arr = new Array(to - from + 1);
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for (var i = 0; i < arr.length; i++) {
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arr[i] = from + i;
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}
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return arr;
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};

‎src/views/base.js‎

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@@ -9,6 +9,11 @@ class BaseView extends abstractMatrix() {
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this.rows = rows;
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this.columns = columns;
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}
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// Native array methods should return instances of Array, not Matrix
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static get[Symbol.species]() {
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return require('../matrix');
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}
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}
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module.exports = BaseView;

‎src/views/sub.js‎

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@@ -0,0 +1,34 @@
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'use strict';
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var BaseView = require('./base');
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var util = require('../util');
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class MatrixSubView extends BaseView {
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constructor(matrix, rowIndices, columnIndices, startColumn, endColumn) {
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var rowI, columnI;
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if(typeof rowIndices === 'number') {
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var startRow = rowIndices, endRow = columnIndices;
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util.checkRange(matrix, startRow, endRow, startColumn, endColumn);
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rowI = util.getRange(startRow, endRow);
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columnI = util.getRange(startColumn, endColumn);
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} else {
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var indices = util.checkIndices(matrix, rowIndices, columnIndices);
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rowI = indices.row;
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columnI = indices.column;
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}
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super(matrix, rowI.length, columnI.length);
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this.rowIndices = rowI;
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this.columnIndices = columnI;
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}
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set(rowIndex, columnIndex, value) {
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this.matrix.set(this.rowIndices[rowIndex], this.columnIndices[columnIndex] , value);
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return this;
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}
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get(rowIndex, columnIndex) {
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return this.matrix.get(this.rowIndices[rowIndex], this.columnIndices[columnIndex]);
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}
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}
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module.exports = MatrixSubView;

‎test/views/sub.js‎

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'use strict';
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var Matrix = require('../..');
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describe('Sub view', function () {
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it('should correctly remap coordinates', function () {
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var m = Matrix.ones(5, 8);
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var msv = m.subMatrixView([1,2], [2,1]);
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m.get(1, 2).should.equal(1);
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msv.set(0, 0, 5);
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m.get(1, 2).should.equal(5);
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m.get(2,1).should.equal(1);
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m.set(2,1, 10);
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msv.get(1,1).should.equal(10);
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msv = m.subMatrixView(3,4,6,7);
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m.get(4,7).should.equal(1);
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msv.set(1, 1, 20);
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m.get(4,7).should.equal(20);
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});
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it('should throw when wrong arguments or range', function () {
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var m = Matrix.ones(2,2);
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(function () {
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m.subMatrixView(0,1);
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}).should.throw(TypeError);
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(function () {
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m.subMatrixView(0,1,0,2);
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}).should.throw(RangeError);
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(function () {
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m.subMatrixView([1,1,2], [0,2]);
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}).should.throw(RangeError);
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(function () {
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m.subMatrixView([1,1,2])
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}).should.throw(TypeError);
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});
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});

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