How to represent a 2D matrix in Java?

Question

I have to create in Java a 2D matrix (consisting of double values) as well as a 1D vector. It should be possible to access individual rows and columns as well as individual

Answer 1

You should use Vector for 2D array. It is threadsafe.

Vector>  matrix= new Vector>();

    for(int i=0;i<2;i++){
        Vector r=new Vector<>();
        for(int j=0;j<2;j++){
            r.add(Math.random());
        }
        matrix.add(r);
    }
    for(int i=0;i<2;i++){
        Vector r=matrix.get(i);
        for(int j=0;j<2;j++){
            System.out.print(r.get(j));
        }
        System.out.println();
    }

If this is your matrix indexes

00 01

10 11

You can get specifix index value like this

Double r2c1=matrix.get(1).get(0); //2nd row 1st column

Have a look at Vector