Add new symmetric matrix class and so a new trinagular number method in Sequence class. Modify constructor and the addition routine in matrix classes. Add a new property to WObjekt to store the number of operations.

src/math/matrix/Symmetric.java

@@ -0,0 +1,104 @@
+package math.matrix;
+
+import exception.IllegalDimensionException;
+import math.Sequence;
+
+/**
+ * Symmetric matrix object d<sub>ij</sub>=d<sub>ji</sub>&isin;&#x211D;
+ * with n rows and n columns
+ * @author Daniel Weschke
+ */
+public class Symmetric extends Matrix {
+
+	/**
+	 * UID
+	 */
+	private static final long serialVersionUID = -3506578822884073555L;
+	
+	public Symmetric(int n){
+		this.m = n;
+		this.n = n;
+		data = new double[Sequence.triangularNumber(n)];
+	}
+	
+	public Symmetric(double... d){
+		this((int)Math.ceil(Sequence.triangularRoot(d.length)));
+		int i;
+        for(i=0; i<d.length; i++)
+        	set(i, d[i]);
+	}
+	
+	public Matrix set(int i, double d){
+		data[i] = d;
+		return this;
+	}
+	
+	public Matrix set(int i, int j, double d){
+		data[index(i,j)] = d;
+		return this;
+	}
+	
+	public double get(int i, int j){
+		return get(index(i,j));
+	}
+	
+	private int index(int i, int j){
+		return i>j?Sequence.triangularNumber(i)+j:i+Sequence.triangularNumber(j);
+	}
+
+    /**
+     * Adds two matrices of the same dimension (entrywise addition).
+     * The addition of two n-by-n matrices <b>A</b> and <b>B</b>,
+     * is again an n-by-n matrix computed by adding corresponding elements.
+     * @param B matrix
+     * @return <b>C</b> = <b>A</b> + <b>B</b>, entrywise summarized matrix
+     * @throws IllegalDimensionException
+     */
+    public Matrix plus(Matrix B) throws IllegalDimensionException{
+    	checkDimensions(B);
+    	int i,j;
+        Matrix c = createAddition(B);
+        c.newOperation();
+        if(B instanceof Diagonal)
+        	for(i=0; i<m; i++)
+        		for(j=i; j<n; j++){
+        			c.set(i, j, get(i,j)+((Diagonal) B).get(i));
+        			c.operate();
+        		}
+        else if(B instanceof Symmetric)
+        	for(i=0; i<m; i++)
+        		for(j=i; j<n; j++){
+        			c.set(i,j, get(i,j)+B.get(i,j));
+        			c.operate();
+        		}
+        else
+        	for(i=0; i<m; i++)
+        		for(j=0; j<n; j++){
+        			c.set(i,j, get(i,j)+B.get(i,j));
+        			c.operate();
+        		}
+//        System.out.println(this instanceof Symmetric);
+//        System.out.println(B instanceof Symmetric);
+        return c;
+    }
+	
+    public static void main(String[] args){
+		Symmetric s1 = new Symmetric(1.);
+		System.out.println(s1);
+		Symmetric s2 = new Symmetric(1., 2.);
+		System.out.println(s2);
+		Symmetric s3 = new Symmetric(1., 2., 3.);
+		System.out.println(s3);
+		Symmetric s4 = new Symmetric(1., 2., 3., 4.);
+		System.out.println(s4);
+		System.out.println(s4.get(0,2));
+		System.out.println(s4.get(2,0));
+		try {
+			System.out.println(s2.plus(s3));
+			System.out.println("Operations: "+s2.plus(s3).getOperationsTotal());
+			System.out.println(s2.minus(s3));
+		} catch (IllegalDimensionException e) {
+			e.printStackTrace();
+		}
+	}
+}