public double set(int index, double e) {
        rangeCheck(index);

        double oldValue = elementData[index];

        elementData[index] = e;

        return oldValue;
    }
public double set ( int index , double e ) { rangeCheck ( index ) ; double oldValue = elementData [ index ] ; elementData [ index ] = e ; return oldValue ; }
@param index
@param e
@return the old value in the specified position.