From: hartmann Date: Wed, 29 Jun 2005 15:51:35 +0000 (+0000) Subject: Add comment on ordering of shape functions and definition of eta and zeta. X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=89329efc160e575541a16c3d54cd85a7aff962e7;p=dealii-svn.git Add comment on ordering of shape functions and definition of eta and zeta. git-svn-id: https://svn.dealii.org/trunk@10972 0785d39b-7218-0410-832d-ea1e28bc413d --- diff --git a/deal.II/deal.II/source/grid/tria_accessor.cc b/deal.II/deal.II/source/grid/tria_accessor.cc index 40bf7421e7..48df4c7b74 100644 --- a/deal.II/deal.II/source/grid/tria_accessor.cc +++ b/deal.II/deal.II/source/grid/tria_accessor.cc @@ -906,6 +906,13 @@ Point<3> TriaObjectAccessor<3, 3>::barycenter () const \vec x_s = 1/|K| \int_K \vec x dx dy dz = 1/|K| \int_{\hat K} \vec x(xi,eta,zeta) |det J| d(xi) d(eta) d(zeta) + Note, that in the ordering of the shape functions tphi[0]-tphi[7] + below, eta and zeta have been exchanged (zeta belongs to the y, and + eta to the z direction). However, the resulting Jacobian determinant + detJ should be the same, as a matrix and the matrix created from it + by exchanging two consecutive lines and two neighboring columns have + the same determinant. + # x, y and z are arrays holding the x-, y- and z-values of the four vertices # of this cell in real space. x := array(0..7):