code: public void mutableDivide(double c, double d)
      {
          final double[] r = new double[2];
          cDiv(real, imag, c, d, r);
          this.real = r[0];
          this.imag = r[1];
      }
docs: Alters this complex number as if a division by another complex number was performed.
  @param c the real part of the other number
  @param d the imaginary part of the other number