code: public static void mult( DMatrix5x5 a , DMatrix5 b , DMatrix5 c) {
          c.a1 = a.a11*b.a1 + a.a12*b.a2 + a.a13*b.a3 + a.a14*b.a4 + a.a15*b.a5;
          c.a2 = a.a21*b.a1 + a.a22*b.a2 + a.a23*b.a3 + a.a24*b.a4 + a.a25*b.a5;
          c.a3 = a.a31*b.a1 + a.a32*b.a2 + a.a33*b.a3 + a.a34*b.a4 + a.a35*b.a5;
          c.a4 = a.a41*b.a1 + a.a42*b.a2 + a.a43*b.a3 + a.a44*b.a4 + a.a45*b.a5;
          c.a5 = a.a51*b.a1 + a.a52*b.a2 + a.a53*b.a3 + a.a54*b.a4 + a.a55*b.a5;
      }
docs: <p>Performs matrix to vector multiplication:<br>
  <br>
  c = a * b <br>
  <br>
  c<sub>i</sub> = &sum;<sub>k=1:n</sub> { a<sub>ik</sub> * b<sub>k</sub>}
  </p>
  
  @param a The left matrix in the multiplication operation. Not modified.
  @param b The right vector in the multiplication operation. Not modified.
  @param c Where the results of the operation are stored. Modified.