public class OrdinaryMatrix extends Matrix {
	//Data-elements
	private double[][] elements; 
	
	//Constructors
	public OrdinaryMatrix(int rows,int cols) {
		n=rows;
		m=cols; 
		elements=new double[n][m];
	}
		
    public OrdinaryMatrix(double[][] data) {
    	this(data.length,data[0].length);
        for (int i = 0; i < data.length; i++)
            for (int j = 0; j < data[0].length; j++)
                    elements[i][j]=data[i][j];
    }
    
    public OrdinaryMatrix(Matrix arg) {
    	this(arg.getRows(),arg.getColumns());
        for (int i = 1; i <= arg.getRows(); i++)
            for (int j = 1; j <= arg.getColumns(); j++)
                    elements[i-1][j-1]=arg.elementAt(i,j);
    }    

	//Protected method f - inherited from Matrix
	
	//Implementation of abstract methods
	public double elementAt(int i,int j) {
		f(i,j);
     	return elements[i-1][j-1];
    }
    
    public double setElementAt(int i,int j,double value) {
    	f(i,j);
        double oldValue=elements[i-1][j-1];
     	elements[i-1][j-1]=value;
     	return oldValue;
    }
    
    protected Matrix create(int rows,int cols) {
    	return new OrdinaryMatrix(rows,cols);
    }
	   
    //Public methods - inherited from Matrix	
}