From: Wolfgang Bangerth Date: Wed, 24 Apr 2002 12:02:22 +0000 (+0000) Subject: Clarify docs for the "interpolate" function. X-Git-Tag: v8.0.0~18124 X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6884d6d316650549338f36d568a16836bd80bba1;p=dealii.git Clarify docs for the "interpolate" function. git-svn-id: https://svn.dealii.org/trunk@5724 0785d39b-7218-0410-832d-ea1e28bc413d --- diff --git a/deal.II/deal.II/include/fe/fe_tools.h b/deal.II/deal.II/include/fe/fe_tools.h index 999af674ed..6a45e7090e 100644 --- a/deal.II/deal.II/include/fe/fe_tools.h +++ b/deal.II/deal.II/include/fe/fe_tools.h @@ -126,31 +126,52 @@ class FETools * Therefore the meanvalue is taken * at the DoF values on the * discontinuities. + * + * Note that the resulting output + * vector does not necessarily + * respect continuity + * requirements at hanging nodes: + * if, for example, you are + * interpolating a Q2 field to a + * Q1 field, then at hanging + * nodes the output field will + * have the function value of the + * input field, which however is + * not usually the mean value of + * the two adjacent nodes. It is + * thus not part of the Q1 + * function space on the whole + * triangulation, although it is + * of course Q1 on each cell. */ template - static void interpolate(const DoFHandler &dof1, - const Vector &u1, - const DoFHandler &dof2, - Vector &u2); + static void interpolate (const DoFHandler &dof1, + const Vector &u1, + const DoFHandler &dof2, + Vector &u2); /** - * Gives the interpolation of the @p{fe1}- - * function @p{u1} to a @p{fe2}-function, and + * Gives the interpolation of the + * @p{fe1}-function @p{u1} to a + * @p{fe2}-function, and * interpolates this to a second - * @p{fe1}-function named @p{u1_interpolated}. + * @p{fe1}-function named + * @p{u1_interpolated}. * * Note, that this function only - * makes sense if the finite element - * space due to @p{fe1} is not a subset of - * the finite element space due to - * @p{fe2}, as if it were a subset then - * @p{u1_interpolated} would be equal to @p{u1}. + * makes sense if the finite + * element space due to @p{fe1} + * is not a subset of the finite + * element space due to @p{fe2}, + * as if it were a subset then + * @p{u1_interpolated} would be + * equal to @p{u1}. */ template - static void back_interpolate(const DoFHandler &dof1, - const Vector &u1, - const FiniteElement &fe2, - Vector &u1_interpolated); + static void back_interpolate (const DoFHandler &dof1, + const Vector &u1, + const FiniteElement &fe2, + Vector &u1_interpolated); /** * Gives $(Id-I_h)z2$ for a given