code: public static void divide( DMatrix3x3 a , double alpha ) {
          a.a11 /= alpha; a.a12 /= alpha; a.a13 /= alpha;
          a.a21 /= alpha; a.a22 /= alpha; a.a23 /= alpha;
          a.a31 /= alpha; a.a32 /= alpha; a.a33 /= alpha;
      }
docs: <p>
  Performs an in-place element by element scalar division. Scalar denominator.<br>
  <br>
  a<sub>ij</sub> = a<sub>ij</sub>/&alpha;
  </p>
  
  @param a The matrix whose elements are to be divided.  Modified.
  @param alpha the amount each element is divided by.