[Cleanup] Cosmetics

src/timestepping/newmark.cc

@@ -106,10 +106,12 @@ void Newmark<VectorType, MatrixType, FunctionType, dim>::postProcess(
 
   v = problem_iterate;
 
+  // u1 = tau/2 ( v1 + v0 ) + u0
   u = u_o;
   Arithmetic::addProduct(u, tau / 2.0, v);
   Arithmetic::addProduct(u, tau / 2.0, v_o);
 
+  // a1 = 2/tau ( v1 - v0 ) - a0
   a = 0;
   Arithmetic::addProduct(a, 2.0 / tau, v);
   Arithmetic::subtractProduct(a, 2.0 / tau, v_o);