java 矩阵运算源代码

以下是 Java 实现的矩阵运算的源代码：

public class Matrix {
    private int rows;
    private int columns;
    private double[][] data;

    public Matrix(int rows, int columns) {
        this.rows = rows;
        this.columns = columns;
        this.data = new double[rows][columns];
    }

    public Matrix(double[][] data) {
        this.rows = data.length;
        this.columns = data[0].length;
        this.data = new double[rows][columns];
        for (int i = 0; i < rows; i++) {
            for (int j = 0; j < columns; j++) {
                this.data[i][j] = data[i][j];
            }
        }
    }

    public int getRows() {
        return rows;
    }

    public int getColumns() {
        return columns;
    }

    public double[][] getData() {
        return data;
    }

    public void set(int row, int column, double value) {
        data[row][column] = value;
    }

    public double get(int row, int column) {
        return data[row][column];
    }

    public Matrix add(Matrix other) {
        if (rows != other.rows || columns != other.columns) {
            throw new IllegalArgumentException("Matrices must have the same dimensions");
        }
        Matrix result = new Matrix(rows, columns);
        for (int i = 0; i < rows; i++) {
            for (int j = 0; j < columns; j++) {
                result.set(i, j, data[i][j] + other.get(i, j));
            }
        }
        return result;
    }

    public Matrix subtract(Matrix other) {
        if (rows != other.rows || columns != other.columns) {
            throw new IllegalArgumentException("Matrices must have the same dimensions");
        }
        Matrix result = new Matrix(rows, columns);
        for (int i = 0; i < rows; i++) {
            for (int j = 0; j < columns; j++) {
                result.set(i, j, data[i][j] - other.get(i, j));
            }
        }
        return result;
    }

    public Matrix multiply(Matrix other) {
        if (columns != other.rows) {
            throw new IllegalArgumentException("Matrices are not compatible for multiplication");
        }
        Matrix result = new Matrix(rows, other.columns);
        for (int i = 0; i < rows; i++) {
            for (int j = 0; j < other.columns; j++) {
                double sum = 0;
                for (int k = 0; k < columns; k++) {
                    sum += data[i][k] * other.get(k, j);
                }
                result.set(i, j, sum);
            }
        }
        return result;
    }

    public Matrix transpose() {
        Matrix result = new Matrix(columns, rows);
        for (int i = 0; i < rows; i++) {
            for (int j = 0; j < columns; j++) {
                result.set(j, i, data[i][j]);
            }
        }
        return result;
    }

    public void print() {
        for (int i = 0; i < rows; i++) {
            for (int j = 0; j < columns; j++) {
                System.out.print(data[i][j] + " ");
            }
            System.out.println();
        }
    }
}

这个类包含了矩阵的基本运算，如加法、减法、乘法和转置。可以使用以下代码来测试这个类的功能：

public static void main(String[] args) {
    double[][] data1 = {{1, 2, 3}, {4, 5, 6}};
    double[][] data2 = {{7, 8}, {9, 10}, {11, 12}};

    Matrix matrix1 = new Matrix(data1);
    Matrix matrix2 = new Matrix(data2);

    Matrix sum = matrix1.add(matrix2);
    System.out.println("Sum:");
    sum.print();

    Matrix difference = matrix1.subtract(matrix2);
    System.out.println("Difference:");
    difference.print();

    Matrix product = matrix1.multiply(matrix2);
    System.out.println("Product:");
    product.print();

    Matrix transpose = matrix1.transpose();
    System.out.println("Transpose:");
    transpose.print();
}