This article describes the implementation of matrices such as addition, subtraction, multiplication, and division, and transformation in Java. Share it for your reference, as follows:
Beginners in Java, write matrix budget programs as tools for use when writing algorithms in the future.
public class MatrixOperation { public static int[][] add(int[][] matrix_a, int[][] matrix_b) { int row = matrix_a.length; int col = matrix_a[0].length; int[][] result = new int[row][col]; if (row != matrix_b.length || col != matrix_b[0].length) { System.out.println("Fault"); } else { for (int i = 0; i < row; i++) { for (int j = 0; j < col; j++) { result[i][j] = matrix_a[i][j] + matrix_b[i][j]; } } } return result; } public static int[][] sub(int[][] matrix_a, int[][] matrix_b) { int row = matrix_a.length; int col = matrix_a[0].length; int[][] result = new int[row][col]; if (row != matrix_b.length || col != matrix_b[0].length) { System.out.println("Fault"); } else { for (int i = 0; i < row; i++) { for (int j = 0; j < col; j++) { result[i][j] = matrix_a[i][j] - matrix_b[i][j]; } } } return result; } public static int[][] dot(int[][] matrix_a, int[][][] matrix_b) { /* * matrix_a's dimension m*p matrix_b's dimension p*n. return dimension * m*n */ int row = matrix_a.length; int col = matrix_a[0].length; int[][] result = new int[row][col]; if (col != matrix_b.length) { System.out.println("Fault"); } else { for (int i = 0; i < row; i++) { for (int j = 0; j < col; j++) { result[i][j] = 0; for (int k = 0; k < col; k++) { result[i][j] += matrix_a[i][k] * matrix_b[k][j]; } } } } return result; } public static int[][] dot(int[][] matrix_a, int b) { int row = matrix_a.length; int col = matrix_a[0].length; int[][] result = new int[row][col]; for (int i = 0; i < row; i++) { for (int j = 0; j < col; j++) { result[i][j] = matrix_a[i][j] * b; } } return result; } public static int[][] mul(int[][] matrix_a, int[][] matrix_b) { /* * matrix_a's dimension m*n matrix_b's dimension m*n. return dimension * m*n */ int row = matrix_a.length; int col = matrix_a[0].length; int[][] result = new int[row][col]; if (row != matrix_b.length || col != matrix_b[0].length) { System.out.println("Fault"); } else { for (int i = 0; i < row; i++) { for (int j = 0; j < col; j++) { result[i][j] = matrix_a[i][j] * matrix_b[i][j]; } } return result; } public static int[][] transport(int[][] matrix_a) { int row = matrix_a.length; int col = matrix_a[0].length; int[][] result = new int[row][col]; for (int i = 0; i < row; i++) { for (int j = 0; j < col; j++) { result[j][i] = matrix_a[i][j]; } } return result; } public static void print(int[][] matrix) { int row = matrix.length; int col = matrix[0].length; for (int i = 0; i < row; i++) { System.out.print("["); for (int j = 0; j < col; j++) { System.out.print(matrix[i][j]); if (j != col - 1) { System.out.print(", "); } } System.out.print("]/n"); } } public static void main(String[] args) { int[][] a = { { 1, 2 }, { 3, 4 } }; int[][] b = { { 7, 8 }, { 6, 5 } }; int[][] c = add(a, b); System.out.println("Wulin.com test results are as follows:"); System.out.println("matrix a = "); print(a); System.out.println("matrix b = "); print(b); System.out.println("matrix a + b = "); print(c); c = sub(a, b); System.out.println("matrix a - b = "); print(c); int[][] d = dot(a, b); System.out.println("matrix a dot b = "); print(d); int[][] e = dot(a, 3); System.out.println("matrix a * 3 = "); print(e); int[][] f = transport(a); System.out.println("matrix aT = "); print(f); int[][] g = mul(a, b); System.out.println("matrix a * b = "); print(g); }}Running results:
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I hope this article will be helpful to everyone's Java programming.