1 function mesh=Umeshproperties(mesh)
4 % mesh=Umeshproperties(mesh)
5 % precomputes some useful mesh properties
10 % This file is part of
12 % SECS2D - A 2-D Drift--Diffusion Semiconductor Device Simulator
13 % -------------------------------------------------------------------
14 % Copyright (C) 2004-2006 Carlo de Falco
18 % SECS2D is free software; you can redistribute it and/or modify
19 % it under the terms of the GNU General Public License as published by
20 % the Free Software Foundation; either version 2 of the License, or
21 % (at your option) any later version.
23 % SECS2D is distributed in the hope that it will be useful,
24 % but WITHOUT ANY WARRANTY; without even the implied warranty of
25 % MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
26 % GNU General Public License for more details.
28 % You should have received a copy of the GNU General Public License
29 % along with SECS2D; If not, see <http://www.gnu.org/licenses/>.
34 weight = [1/3 1/3 1/3];
36 Nelements = Ucolumns(mesh.t);
38 jac([1,2],:) = [mesh.p(1,mesh.t(2,:))-mesh.p(1,mesh.t(1,:));
39 mesh.p(1,mesh.t(3,:))-mesh.p(1,mesh.t(1,:))];
40 jac([3,4],:) = [mesh.p(2,mesh.t(2,:))-mesh.p(2,mesh.t(1,:));
41 mesh.p(2,mesh.t(3,:))-mesh.p(2,mesh.t(1,:))];
42 jacdet = jac(1,:).*jac(4,:)-jac(2,:).*jac(3,:);
44 degen=find(jacdet <= 0);
46 fprintf(1,'invalid mesh element: %d fixing...\n',degen);
47 mesh.t(1:3,degen) = mesh.t([2,1,3],degen);
48 jac([1,2],degen) = [mesh.p(1,mesh.t(2,degen))-mesh.p(1,mesh.t(1,degen));
49 mesh.p(1,mesh.t(3,degen))-mesh.p(1,mesh.t(1,degen))];
50 jac([3,4],degen) = [mesh.p(2,mesh.t(2,degen))-mesh.p(2,mesh.t(1,degen));
51 mesh.p(2,mesh.t(3,degen))-mesh.p(2,mesh.t(1,degen))];
52 jacdet(degen) = jac(1,degen).*jac(4,degen)-jac(2,degen).*jac(3,degen);
56 mesh.wjacdet(inode,:) = areakk .* jacdet .* weight(inode);
61 x0 = mesh.p(1,mesh.t(1,:));
62 y0 = mesh.p(2,mesh.t(1,:));
63 x1 = mesh.p(1,mesh.t(2,:));
64 y1 = mesh.p(2,mesh.t(2,:));
65 x2 = mesh.p(1,mesh.t(3,:));
66 y2 = mesh.p(2,mesh.t(3,:));
68 denom = (-(x1.*y0) + x2.*y0 + x0.*y1 - x2.*y1 - x0.*y2 + x1.*y2);
69 mesh.shg(1,1,:) = (y1 - y2)./denom;
70 mesh.shg(2,1,:) = -(x1 - x2)./denom;
71 mesh.shg(1,2,:) = -(y0 - y2)./denom;
72 mesh.shg(2,2,:) = (x0 - x2)./denom;
73 mesh.shg(1,3,:) = (y0 - y1)./denom;
74 mesh.shg(2,3,:) = -(x0 - x1)./denom;