From f2313f906a14e605701e16c2a269a4393cd72909 Mon Sep 17 00:00:00 2001 From: bonito Date: Thu, 6 Jan 2011 15:21:36 +0000 Subject: [PATCH] git-svn-id: https://svn.dealii.org/trunk@23135 0785d39b-7218-0410-832d-ea1e28bc413d --- deal.II/examples/step-38/doc/intro.dox | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/deal.II/examples/step-38/doc/intro.dox b/deal.II/examples/step-38/doc/intro.dox index 4fb138d76b..bcdf18fee1 100644 --- a/deal.II/examples/step-38/doc/intro.dox +++ b/deal.II/examples/step-38/doc/intro.dox @@ -192,10 +192,8 @@ solution. Since the solution function and its numerical approximation are only defined on the manifold, the obvious definition of this error functional is $| e |_{H^1(\Gamma)} = | \nabla_\Gamma e |_{L_2(\Gamma)} - = \left( \int_\Gamma | \left[\mathbf 1 - \mathbf n \otimes \mathbf -n\right]\nabla (u-u_h) |^2 \right)^{1/2}$. This requires us to provide the -tangential gradient $\left[\mathbf 1 - \mathbf n \otimes \mathbf -n\right]\nabla u$ to the function VectorTools::integrate_difference + = \left( \int_\Gamma | \nabla_\Gamma (u-u_h) |^2 \right)^{1/2}$. This requires us to provide the +tangential gradient to the function VectorTools::integrate_difference (first introduced in step-7), which we will do by implementing the function Solution::gradient in the program below. -- 2.39.5