@Test
public void testGetInversed() throws Exception {
Matrix a =
new Matrix(
new double[][] {
{2, 1, 1},
{1, -1, -1},
{1, 2, 1}
});
Matrix c = a.getInversed();
Matrix r =
new Matrix(
new double[][] {
{1.0 / 3.0, 1.0 / 3.0, 0},
{-(2.0 / 3.0), 1.0 / 3.0, 1},
{1, -1, -1}
});
for (int i = 0; i < c.getNumRows(); i++) {
for (int j = 0; j < c.getNumColumns(); j++) {
assertEquals(r.getElement(i, j), c.getElement(i, j), 0);
}
}
}
@Test
public void testGetCoMatrix() throws Exception {
Matrix a =
new Matrix(
new double[][] {
{1, 2, 3},
{4, 5, 6},
{5, 4, 3}
});
Matrix c = a.getCoMatrix();
Matrix r =
new Matrix(
new double[][] {
{-9, 18, -9},
{6, -12, 6},
{-3, 6, -3}
});
for (int i = 0; i < c.getNumRows(); i++) {
for (int j = 0; j < c.getNumColumns(); j++) {
assertEquals(r.getElement(i, j), c.getElement(i, j), 0);
}
}
}
@Test
public void testGetTransposed() throws Exception {
Matrix a =
new Matrix(
new double[][] {
{1, 2, 3},
{3, 2, 1},
{2, 1, 3}
});
Matrix c = a.getTransposed();
Matrix r =
new Matrix(
new double[][] {
{1, 3, 2},
{2, 2, 1},
{3, 1, 3}
});
for (int i = 0; i < c.getNumRows(); i++) {
for (int j = 0; j < c.getNumColumns(); j++) {
assertEquals(r.getElement(i, j), c.getElement(i, j), 0);
}
}
}
@Test
public void testScalarProduct() throws Exception {
Matrix a = new Matrix(new double[][] {{1, 2, 3}, {3, 2, 1}, {2, 1, 3}});
Matrix b = a.scalarProduct(3);
Matrix r = new Matrix(new double[][] {{3, 6, 9}, {9, 6, 3}, {6, 3, 9}});
for (int i = 0; i < b.getNumRows(); i++) {
for (int j = 0; j < b.getNumColumns(); j++) {
assertEquals(r.getElement(i, j), b.getElement(i, j), 0);
}
}
}
@Test
public void testAddShouldPass() throws Exception {
Matrix a = new Matrix(new double[][] {{1, 2, 3}, {3, 2, 1}, {2, 1, 3}});
Matrix b = new Matrix(new double[][] {{1, 2, 3}, {3, 2, 1}, {2, 1, 3}});
Matrix c = a.add(b);
Matrix r = new Matrix(new double[][] {{2, 4, 6}, {6, 4, 2}, {4, 2, 6}});
for (int i = 0; i < c.getNumRows(); i++) {
for (int j = 0; j < c.getNumColumns(); j++) {
assertEquals(r.getElement(i, j), c.getElement(i, j), 0);
}
}
}
@Test
public void testMatrixMultiplication() throws Exception {
Matrix a = new Matrix(new double[][] {{1, 2, 3}, {3, 2, 1}, {2, 1, 3}});
Matrix b = new Matrix(new double[][] {{4, 5, 6}, {6, 5, 4}, {4, 6, 5}});
Matrix c = a.matrixMultiplication(b);
Matrix r = new Matrix(new double[][] {{28, 33, 29}, {28, 31, 31}, {26, 33, 31}});
for (int i = 0; i < c.getNumRows(); i++) {
for (int j = 0; j < c.getNumColumns(); j++) {
assertEquals(r.getElement(i, j), c.getElement(i, j), 0);
}
}
}
@Test
public void testGetSubmatrix() throws Exception {
Matrix a =
new Matrix(
new double[][] {
{1, 2, 3},
{3, 2, 1},
{2, 1, 3}
});
Matrix b = a.getSubmatrix(1, 1);
Matrix c =
new Matrix(
new double[][] {
{1, 3},
{2, 3}
});
for (int i = 0; i < c.getNumRows(); i++) {
for (int j = 0; j < c.getNumColumns(); j++) {
assertEquals(c.getElement(i, j), b.getElement(i, j), 0);
}
}
}