/usr/share/octave/packages/msh-1.0.10/msh3e_surface_mesh.m is in octave-msh 1.0.10-5.
This file is owned by root:root, with mode 0o644.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 | ## Copyright (C) 2006,2007,2008,2009,2010 Carlo de Falco, Massimiliano Culpo
##
## This file is part of:
## MSH - Meshing Software Package for Octave
##
## MSH is free software; you can redistribute it and/or modify
## it under the terms of the GNU General Public License as published by
## the Free Software Foundation; either version 2 of the License, or
## (at your option) any later version.
##
## MSH is distributed in the hope that it will be useful,
## but WITHOUT ANY WARRANTY; without even the implied warranty of
## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
## GNU General Public License for more details.
##
## You should have received a copy of the GNU General Public License
## along with MSH; If not, see <http://www.gnu.org/licenses/>.
##
## author: Carlo de Falco <cdf _AT_ users.sourceforge.net>
## author: Massimiliano Culpo <culpo _AT_ users.sourceforge.net>
## -*- texinfo -*-
## @deftypefn {Function File} {[@var{emesh},@var{snodes},@var{ssides},@var{striangles}]} = @
## msh3e_surface_mesh(@var{mesh},@var{nsrf},@var{nsides})
##
## Extract the plane surface @var{nsrf} delimited by @var{nsides} from
## @var{mesh}.
##
## Return the vector @var{snodes} containing the references to input
## mesh nodes (field @code{mesh.p}), the vector @var{ssides} containing
## the references to input mesh side (field @code{mesh.s}) and the
## vector @var{striangles} containing the references to input mesh side
## edges (field @code{mesh.e}).
##
## @strong{WARNING}: the suface MUST be ortogonal to either X, Y or Z
## axis. This should be changed to account for generic 2D surface.
##
## @end deftypefn
function [emesh,snodes,ssides,striangles] = msh3e_surface_mesh(mesh,nsrf,nsides)
## Check input
if nargin != 3
error("msh3e_surface_mesh: wrong number of input parameters.");
elseif !(isstruct(mesh) && isfield(mesh,"p") &&
isfield (mesh,"t") && isfield(mesh,"e"))
error("msh3e_surface_mesh: first input is not a valid mesh structure.");
elseif !isscalar(nsrf)
error("msh3e_surface_mesh: second input is not a valid scalar.");
elseif !(isvector(nsides) && isnumeric(nsides))
error("msh3e_surface_mesh: third input is not a valid numeric vector.");
endif
## Surface extraction
## Extraction of 2D surface elements
striangles = find( mesh.e(10,:) == nsrf );
t = mesh.e(1:3,striangles);
tmp = reshape(t,[],1);
## Renumbering
[snodes,ii,jj] = unique(tmp);
nds = 1:length(snodes);
emesh.t = reshape(nds(jj),3,[]);
## Extraction of 2D mesh points
points = mesh.p(:,snodes);
## Test for normals
## FIXME: this should disappear as soon as 2D mesh are not supposed to
## lie on a plane.
if length(unique(points(1,:))) == 1
xyz = [2,3]; # normal to X coordinate
elseif length(unique(points(2,:))) == 1
xyz = [1,3]; # normal to Y coordinate
else
xyz = [1,2]; # normal to Z coordinate
endif
emesh.p = points(xyz,:);
## Extraction of 1D side edges
ssides = [];
for ll = nsides
tmp = find ( mesh.s(3,:) == ll );
ssides = [ssides,tmp];
endfor
nedges = length(ssides);
emesh.e = zeros(7,nedges);
emesh.e(5,:) = mesh.s(3,ssides);
tmp = reshape(mesh.s(1:2,ssides),[],1);
[enodes,nn,mm] = unique(tmp);
[tmp1, nds, tmp2] = intersect(snodes,enodes);
emesh.e(1:2,:) = reshape(nds(mm),2,[]);
## Compute mesh properties
## FIXME: this has to be removed. MSH should not depend on BIM.
emesh = bim2c_mesh_properties(emesh);
endfunction
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