Änderungen Matrix

S01-VL06-Aufgabe 2/Aufgabe.java

@@ -0,0 +1,35 @@
+class Aufgabe {
+  public static void main(String[] args) {
+    Matrix matrix1 = new Matrix(3,1);
+    matrix1.setValue(1,1,5);
+    matrix1.setValue(2,1,4);
+    matrix1.setValue(3,1,8);
+
+    Matrix matrix2 = new Matrix(3,1);
+    matrix2.setValue(1,1,9);
+    matrix2.setValue(2,1,3);
+    matrix2.setValue(3,1,4);
+
+    System.out.println("Matrix 1:");
+    matrix1.print();
+
+    System.out.println("Matrix 2:");
+    matrix2.print();
+
+    System.out.println("Matrix 1 nach Multiplikation mit 5:");
+    matrix1.multiply(5);
+    matrix1.print();
+
+    System.out.println("Matrix 1 nach Addition mit Matrix 2:");
+    matrix1.add(matrix2);
+    matrix1.print();
+
+    System.out.println("Matrix 2 nach Multiplikation mit Matrix 1:");
+    try {
+      matrix2.multiply(matrix2);
+      matrix2.print();
+    } catch(MatrixException e) {
+      System.out.println("Fehler beim Multiplizieren zweier Matrizen: " + e.getMessage());
+    }
+  }
+}

S01-VL06-Aufgabe 2/Matrix.java

@@ -0,0 +1,84 @@
+public class Matrix {
+  private int rows = 0;
+  private int columns = 0;
+  private int[][] matrix;
+
+  Matrix(int rows, int columns) {
+    this.rows = rows;
+    this.columns = columns;
+    this.init();
+  }
+
+  private void init() {
+    this.matrix = new int[this.rows][this.columns];
+
+    for(int r = 0; r < this.rows; r++) {
+      for(int c = 0; c < this.columns; c++) {
+        this.setValue(r+1, c+1, 0);
+      }
+    }
+  }
+
+  int getValue(int row, int column) {
+    return this.matrix[row-1][column-1];
+  }
+
+  int getNumberOfColumns() {
+    return this.columns;
+  }
+
+  int getNumberOfRows() {
+    return this.rows;
+  }
+
+  void setValue(int row, int column, int value) {
+    this.matrix[row-1][column-1] = value;
+  }
+
+  void multiply(int scalar) {
+    for(int r = 0; r < this.rows; r++) {
+      for(int c = 0; c < this.columns; c++) {
+        this.matrix[r][c] *= scalar;
+      }
+    }
+  }
+
+  void multiply(Matrix matrix) {
+    if(isSameSize(matrix)) {
+      for(int r = 0; r < this.rows; r++) {
+        for(int c = 0; c < this.columns; c++) {
+          this.matrix[r][c] *= matrix.getValue(r+1, c+1);
+        }
+      }
+    } else {
+      throw new MatrixException();
+    }
+  }
+
+  boolean isSameSize(Matrix matrix) {
+    return this.getNumberOfColumns() == matrix.getNumberOfColumns() && this.getNumberOfRows() == matrix.getNumberOfRows();
+  }
+
+  void add(Matrix matrix) {
+    if(this.getNumberOfColumns() == matrix.getNumberOfColumns() && this.getNumberOfRows() == matrix.getNumberOfRows()) {
+      for(int r = 0; r < this.rows; r++) {
+        for(int c = 0; c < this.columns; c++) {
+          this.matrix[r][c] += matrix.getValue(r+1, c+1);
+        }
+      }
+    }
+  }
+
+  void print() {
+    for(int r = 0; r < this.rows; r++) {
+      for(int c = 0; c < this.columns; c++) {
+        System.out.printf("%5d", this.getValue(r+1, c+1));
+      }
+      System.out.print("\n");
+    }
+  }
+}
+
+class MatrixException extends RuntimeException {
+
+}