docs: public static void multAddOuter( double alpha , DMatrix4x4 A , double beta , DMatrix4 u , DMatrix4 v , DMatrix4x4 C ) {
          C.a11 = alpha*A.a11 + beta*u.a1*v.a1;
          C.a12 = alpha*A.a12 + beta*u.a1*v.a2;
          C.a13 = alpha*A.a13 + beta*u.a1*v.a3;
          C.a14 = alpha*A.a14 + beta*u.a1*v.a4;
          C.a21 = alpha*A.a21 + beta*u.a2*v.a1;
          C.a22 = alpha*A.a22 + beta*u.a2*v.a2;
          C.a23 = alpha*A.a23 + beta*u.a2*v.a3;
          C.a24 = alpha*A.a24 + beta*u.a2*v.a4;
          C.a31 = alpha*A.a31 + beta*u.a3*v.a1;
          C.a32 = alpha*A.a32 + beta*u.a3*v.a2;
          C.a33 = alpha*A.a33 + beta*u.a3*v.a3;
          C.a34 = alpha*A.a34 + beta*u.a3*v.a4;
          C.a41 = alpha*A.a41 + beta*u.a4*v.a1;
          C.a42 = alpha*A.a42 + beta*u.a4*v.a2;
          C.a43 = alpha*A.a43 + beta*u.a4*v.a3;
          C.a44 = alpha*A.a44 + beta*u.a4*v.a4;
      }