public AttributeVector response() {
        double[] y = new double[data.size()];
        for (int i = 0; i < y.length; i++) {
            y[i] = data.get(i).y;
        }
        return new AttributeVector(response, y);
    }
public AttributeVector response ( ) { double [ ] y = new double [ data . size ( ) ] ; for ( int i = 0 ; i < y . length ; i ++ ) { y [ i ] = data . get ( i ) . y ; } return new AttributeVector ( response , y ) ; }
Returns the response attribute vector. null means no response
variable in this dataset.
@return the response attribute vector. null means no response
variable in this dataset.