# How to generate Q4 element mesh in selected area?

3 visualizaciones (últimos 30 días)
waqas el 8 de Sept. de 2021
Respondida: darova el 8 de Sept. de 2021
Hi,
I have a region ( variable 'nmask' in the .MAT file) on which I want to generate a Q4 mesh. In my current implementation, the nodes are not falling perfectly on the boundary of the region. Figure below should explain it further where red markers show the location of the nodes. Following code was used to generate these:
tx = mfc:subset:mlc;
ty = mfr:subset:mlr;
[TX,TY] = meshgrid(tx,ty);
nodeDetails = [(1:size(TX,1)*size(TX,2))', TY(:),TX(:)];
%Connectivity Matrix
c = 0;
conect = zeros((size(TX,1)-1)*(size(TX,2)-1),4);
for j = 0:(size(TX,2)-2)
for i = 1: size(TX,1)-1
c = c + 1;
ii = j*(size(TX,1)) + i;
conect(c,:) = [ii, ii + 1, ii + size(TX,1) + 1, ii + size(TX,1)];
end
end
I am only interested in the white region. How can I also discard the other points?
##### 0 comentariosMostrar -2 comentarios más antiguosOcultar -2 comentarios más antiguos

Iniciar sesión para comentar.

darova el 8 de Sept. de 2021
x = [-10:-8 -7:7 8:10];
y = [-8:-6 -5:5 6:8];
[X,Y] = meshgrid(x,y);
i1 = -8<X & X<8 & -6<Y & Y<6; % inside region
i2 = X<0 & abs(Y)<2; % small hole right side
ind = i1 | i2;
Z = X*0;
Z(ind) = nan; % remove inside part
plot(X(:),Y(:),'.r') % whole mesh
surface(X,Y,Z)
view(45,45)
##### 0 comentariosMostrar -2 comentarios más antiguosOcultar -2 comentarios más antiguos

Iniciar sesión para comentar.

### Categorías

Más información sobre Computational Geometry en Help Center y File Exchange.

### Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by