Matriks.java

public class Matrix {
    private int mat[][], x, y;

    Matrix() {
    mat = new int[0][0];
    x = 0;
    y = 0;
    }

    Matrix(int x) {
    mat = new int[x][x];
    for (int i = 0; i < x; i++) mat[i][i] = 1;
    this.x = x;
    y = x;
    }

    Matrix(int x, int y) {
    mat = new int[y][x];
    this.x = x;
    this.y = y;
    }

    void setElementAt(int x, int y, int data) {
    mat[x][y] = data;
    }


    int getElementAt(int x, int y) {
    return mat[x][y];
    }

    int getRow() {
    return x;
    }

    int getColumn() {
    return y;
    }

    void print() {
    for (int i = 0; i < y; i++) {
        for (int j = 0; j < x; j++) {
        System.out.print(mat[i][j] + " ");
        }
        System.out.println();
    }
    }

    int[][] toIntArray() {
    return mat;
    }

    void setSize(int m, int n) {
    int[][] temp = new int[n][m];
    for (int i = 0; i < Math.min(n, y); i++) System.arraycopy(mat[i], 0, temp[i], 0, Math.min(x, m));
    mat = temp;
    x = m;
    y = n;
    }

    void transpose() {
    int matT[][] = new int[x][y];
    for (int i = 0; i < y; i++) for (int j = 0; j < x; j++) matT[j][i] = mat[i][j];
    mat = matT;
    int temp = x;
    x = y;
    y = temp;
    }

    void toIdentity(int x) {
    mat = new int[x][x];
    for (int i = 0; i < x; i++) mat[i][i] = 1;
    this.x = x;
    y = x;
    }

    void add(Matrix m) {
    for (int i = 0; i < y; i++) for (int j = 0; j < x; j++) {
        try {
        mat[i][j] += m.getElementAt(i, j);
        }
        catch (Exception e) {
        throw new IllegalArgumentException("Matrices size mismatch");
        }
    }
    }

    void add(Matrix m, Matrix n) {
    Matrix temp = new Matrix(m.getRow(), m.getColumn());
    for (int i = 0; i < y; i++) for (int j = 0; j < x; j++) {
        try {
        temp.setElementAt(i, j, m.getElementAt(i, j) + n.getElementAt(i, j));
        }
        catch (Exception e) {
        throw new IllegalArgumentException("Matrices size mismatch");
        }
    }
    mat = temp.toIntArray();
    x = m.getRow();
    y = m.getColumn();
    }

    void subtract(Matrix m) {
    for (int i = 0; i < y; i++) for (int j = 0; j < x; j++) {
        try {
        mat[i][j] -= m.getElementAt(i, j);
        }
        catch (Exception e) {
        throw new IllegalArgumentException("Matrices size mismatch");
        }
    }
    }

    void subtract(Matrix m, Matrix n) {
    Matrix temp = new Matrix(m.getRow(), m.getColumn());
    for (int i = 0; i < y; i++) for (int j = 0; j < x; j++) {
        try {
        temp.setElementAt(i, j, m.getElementAt(i, j) - n.getElementAt(i, j));
        }
        catch (Exception e) {
        throw new IllegalArgumentException("Matrices size mismatch");
        }
    }
    mat = temp.toIntArray();
    x = m.getRow();
    y = m.getColumn();
    }

    void multiply(Matrix m) {
    for (int i = 0; i < y; i++) for (int j = 0; j < x; j++) {
        int jumlah = 0;
        for (int k = 0; k < x; k++) {
        try {
            jumlah += mat[i][k] * m.getElementAt(k, j);
        }
        catch (Exception e) {
            throw new IllegalArgumentException("Matrices size mismatch");
        }
        }
        mat[i][j] = jumlah;
    }
    }

    void multiply(Matrix m, Matrix n) {
    for (int i = 0; i < y; i++) for (int j = 0; j < x; j++) {
        int jumlah = 0;
        for (int k = 0; k < x; k++) {
        try {
            jumlah += m.getElementAt(i, k) * n.getElementAt(k, j);
        }
        catch (Exception e) {
            throw new IllegalArgumentException("Matrices size mismatch");
        }
        }
        mat[i][j] = jumlah;
    }
    }
}