code: public static Vector multiply(Vector left, Vector right) {
          if (left.length() != right.length())
              throw new IllegalArgumentException(
                      "Vectors of different sizes cannot be multiplied");
          int length = left.length();
          for (int i = 0; i < length; ++i)
              left.set(i, left.getValue(i).doubleValue() *
                          right.getValue(i).doubleValue());
          return left;
      }
docs: Mulitplies the values in {@code left} and {@code right} and store the
  product in {@code left}.  This is an element by element multiplication.
  
  @param left The left {@code Vector} to multiply, and contain the result
  values.
  @param right The right {@code Vector} to multiply.
  
  @return The product of {@code left} and {@code right}