docs: public static void multAddOuter( double alpha , DMatrix2x2 A , double beta , DMatrix2 u , DMatrix2 v , DMatrix2x2 C ) {
          C.a11 = alpha*A.a11 + beta*u.a1*v.a1;
          C.a12 = alpha*A.a12 + beta*u.a1*v.a2;
          C.a21 = alpha*A.a21 + beta*u.a2*v.a1;
          C.a22 = alpha*A.a22 + beta*u.a2*v.a2;
      }