fem_interpol_local.m

function df = fem_interpol_local(f, df, params)
%function df = fem_interpol_local(f, df, params)
%
% function interpolating the given analytical function with 
% local evaluation f(grid,elids,lcoord,params) into the allocated discrete
% function df
% by this, also discrete functions on the same grid with possibly
% other polynomial degree or other discrete function type can 
% be interpolated.

% B. Haasdonk 12.1.2011

% for all lagrange nodes evaluate f and set as dof

if nargin<3
  params = [];
end;

lagrange_nodes = lagrange_nodes_lcoord(df.pdeg); 

% possibly multiple evaluation in edge nodes, accept for now. 
for i = 1:size(lagrange_nodes,1);
  gids = df.df_info.global_dof_index(1:df.grid.nelements, i);
%  glob = local2global(df.grid, 1:df.grid.nelements, lagrange_nodes(i,:));
  fs = f(df.grid,1:df.grid.nelements,lagrange_nodes(i,:),params);
  df.dofs(gids) = fs;
end;