/*
* Copyright 2000-2016 JetBrains s.r.o.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.intellij.util;
import junit.framework.TestCase;
/**
* @author Sergey.Malenkov
*/
public class MatrixTest extends TestCase {
public void testCreate() {
Matrix matrix = Matrix.create(3, /*row:*/ 11, 21, /*row:*/ 12, 22, /*row:*/ 13, 23);
int width = matrix.getColumns();
assertEquals(2, width);
int height = matrix.getRows();
assertEquals(3, height);
for (int w = 0; w < width; w++) {
for (int h = 0; h < height; h++) {
assertEquals((double)(10 * (w + 1) + (h + 1)), matrix.get(w, h));
}
}
assertEquals(Vector.create(11, 21), matrix.getRow(0));
assertEquals(Vector.create(12, 22), matrix.getRow(1));
assertEquals(Vector.create(13, 23), matrix.getRow(2));
assertEquals(Vector.create(11, 12, 13), matrix.getColumn(0));
assertEquals(Vector.create(21, 22, 23), matrix.getColumn(1));
}
public void testCreateEmpty() {
try {
fail("Created " + Matrix.create(0));
}
catch (Exception ignored) {
}
}
public void testCreateNull() {
try {
fail("Created " + Matrix.create(0, null));
}
catch (Exception ignored) {
}
}
public void testCreateZeroWidth() {
try {
fail("Created " + Matrix.create(2, 0));
}
catch (Exception ignored) {
}
}
public void testCreateZeroHeight() {
try {
fail("Created " + Matrix.create(0, 0));
}
catch (Exception ignored) {
}
}
public void testCreateIdentity() {
Matrix matrix = Matrix.createIdentity(3);
int width = matrix.getColumns();
assertEquals(3, width);
int height = matrix.getRows();
assertEquals(3, height);
for (int w = 0; w < width; w++) {
for (int h = 0; h < height; h++) {
assertEquals((double)(w == h ? 1 : 0), matrix.get(w, h));
}
}
Vector vector0 = Vector.create(1, 0, 0);
assertEquals(vector0, matrix.getRow(0));
assertEquals(vector0, matrix.getColumn(0));
Vector vector1 = Vector.create(0, 1, 0);
assertEquals(vector1, matrix.getRow(1));
assertEquals(vector1, matrix.getColumn(1));
Vector vector2 = Vector.create(0, 0, 1);
assertEquals(vector2, matrix.getRow(2));
assertEquals(vector2, matrix.getColumn(2));
}
public void testCreateIdentityWrong() {
try {
fail("Created " + Matrix.createIdentity(-1));
}
catch (Exception ignored) {
}
}
public void testCreateColumn() {
Vector vector = Vector.create(1, 2, 3);
Matrix matrix = Matrix.createColumn(vector);
assertEquals(1, matrix.getColumns());
assertEquals(3, matrix.getRows());
assertEquals(vector, matrix.getColumn(0));
assertEquals(Vector.create(1), matrix.getRow(0));
assertEquals(Vector.create(2), matrix.getRow(1));
assertEquals(Vector.create(3), matrix.getRow(2));
}
public void testCreateRow() {
Vector vector = Vector.create(1, 2, 3);
Matrix matrix = Matrix.createRow(vector);
assertEquals(3, matrix.getColumns());
assertEquals(1, matrix.getRows());
assertEquals(vector, matrix.getRow(0));
assertEquals(Vector.create(1), matrix.getColumn(0));
assertEquals(Vector.create(2), matrix.getColumn(1));
assertEquals(Vector.create(3), matrix.getColumn(2));
}
public void testPlus() {
// see http://ru.onlinemschool.com/math/library/matrix/add_subtract/
assertEquals(Matrix.create(2, // rows
7, 3,
6, 4), Matrix.create(2, // rows
4, 2,
9, 0).plus(Matrix.create(2, // rows
3, 1,
-3, 4)));
}
public void testPlusWrong() {
try {
fail("Created " + Matrix.create(1, 0).plus(Matrix.create(2, 1, 1, 1, 1)));
}
catch (Exception ignored) {
}
}
public void testMinus() {
// see http://ru.onlinemschool.com/math/library/matrix/add_subtract/
assertEquals(Matrix.create(2, // rows
1, 1,
12, -4), Matrix.create(2, // rows
4, 2,
9, 0).minus(Matrix.create(2, // rows
3, 1,
-3, 4)));
}
public void testMinusWrong() {
try {
fail("Created " + Matrix.create(1, 0).minus(Matrix.create(2, 1, 1, 1, 1)));
}
catch (Exception ignored) {
}
}
public void testMultiplyByValue() {
// see http://ru.onlinemschool.com/math/library/matrix/multiply1/
assertEquals(Matrix.create(2, // rows
20, 10,
45, 0), Matrix.create(2, // rows
4, 2,
9, 0).multiply(5));
assertEquals(Matrix.create(3, // rows
-4, 4,
2, -0.0, // fix
-10, 2), Matrix.create(3, // rows
2, -2,
-1, 0,
5, -1).multiply(-2));
}
public void testMultiplyByMatrix() {
// see http://ru.onlinemschool.com/math/library/matrix/multiply/
assertEquals(Matrix.create(2, // rows
6, 12,
27, 9), Matrix.create(2, // rows
4, 2,
9, 0).multiply(Matrix.create(2, // rows
3, 1,
-3, 4)));
assertEquals(Matrix.create(3, // rows
7, -2, 19,
-15, 3, -18,
23, -4, 17), Matrix.create(3, // rows
2, 1,
-3, 0,
4, -1).multiply(Matrix.create(2, // rows
5, -1, 6,
-3, 0, 7)));
}
public void testMultiplyByVector() {
Vector vector = Vector.create(1, 2, 3);
assertEquals(vector, Matrix.createIdentity(3).multiply(vector));
Matrix matrix = Matrix.create(2, /*row:*/ 11, 12, 13, /*row:*/ 21, 22, 23);
Vector result = matrix.multiply(vector);
assertEquals(Vector.create(74, 134), result);
assertEquals(matrix.getRows(), result.getSize());
assertEquals(Matrix.createColumn(result), matrix.multiply(Matrix.createColumn(vector)));
}
public void testDeterminant() {
// see http://ru.onlinemschool.com/math/library/matrix/determinant/
assertEquals(33.0, Matrix.create(2, 5, 7, -4, 1).determinant());
assertEquals(97.0, Matrix.create(3, 5, 7, 1, -4, 1, 0, 2, 0, 3).determinant());
assertEquals(6.0, Matrix.create(3, 2, 4, 1, 0, 2, 1, 2, 1, 1).determinant());
assertEquals(0.0, Matrix.create(4, 2, 4, 1, 1, 0, 2, 0, 0, 2, 1, 1, 3, 4, 0, 2, 3).determinant());
}
public void testDeterminantZero() {
assertEquals(0.0, Matrix.create(3, 0, 0, 0, 1, 2, 3, 4, 5, 6).determinant()); // 1 zero row
assertEquals(0.0, Matrix.create(3, 1, 1, 1, 1, 1, 1, 1, 2, 3).determinant()); // 2 equal rows
assertEquals(0.0, Matrix.create(3, 1, 1, 1, 2, 2, 2, 1, 2, 3).determinant()); // 2 proportional rows
}
public void testDeterminantIdentity() {
assertEquals(1.0, Matrix.createIdentity(1).determinant());
assertEquals(1.0, Matrix.createIdentity(2).determinant());
assertEquals(1.0, Matrix.createIdentity(3).determinant());
assertEquals(1.0, Matrix.createIdentity(4).determinant());
assertEquals(1.0, Matrix.createIdentity(5).determinant());
}
public void testDeterminantInverse() {
Matrix matrix = Matrix.create(2, 5, 7, -4, 1);
assertEquals(matrix.determinant(), 1 / matrix.inverse().determinant());
}
public void testDeterminantTranspose() {
Matrix matrix = Matrix.create(2, 5, 7, -4, 1);
assertEquals(matrix.determinant(), matrix.transpose().determinant());
}
public void testTranspose() {
Matrix matrix = Matrix.create(3, /*row:*/ 11, 12, /*row:*/ 21, 22, /*row:*/ 31, 32);
Matrix result = matrix.transpose();
assertEquals(matrix.getColumns(), result.getRows());
assertEquals(matrix.getColumn(0), result.getRow(0));
assertEquals(matrix.getColumn(1), result.getRow(1));
assertEquals(matrix.getRows(), result.getColumns());
assertEquals(matrix.getRow(0), result.getColumn(0));
assertEquals(matrix.getRow(1), result.getColumn(1));
assertEquals(matrix.getRow(2), result.getColumn(2));
// see http://ru.onlinemschool.com/math/library/matrix/transpose/
assertEquals(Matrix.create(2, 4, 9, 2, 0), Matrix.create(2, 4, 2, 9, 0).transpose());
assertEquals(Matrix.create(2, 2, -3, 4, 1, 0, -1), Matrix.create(3, 2, 1, -3, 0, 4, -1).transpose());
assertEquals(Matrix.create(3, 2, 1, -3, 0, 4, -1), Matrix.create(2, 2, -3, 4, 1, 0, -1).transpose());
}
public void testTransposeIdentity() {
Matrix matrix = Matrix.create(3, /*row:*/ 11, 12, 13, /*row:*/ 21, 22, 23, /*row:*/ 31, 32, 33);
assertEquals(matrix, Matrix.createIdentity(3).multiply(matrix));
assertEquals(matrix, matrix.multiply(Matrix.createIdentity(3)));
}
public void testInverse() {
Matrix matrix = Matrix.create(2, 5, 7, -4, 1);
assertEquals(matrix, matrix.inverse().inverse());
assertEquals(matrix.transpose().inverse(), matrix.inverse().transpose());
// see http://ru.onlinemschool.com/math/library/matrix/inverse/
assertEquals(Matrix.create(3, //rows
1 / 6.0, -1 / 2.0, 1 / 3.0,
1 / 3.0, 0, -1 / 3.0,
-2 / 3.0, 1, 2 / 3.0), Matrix.create(3, //rows
2, 4, 1,
0, 2, 1,
2, 1, 1).inverse());
}
}