Solving pde for geometry with concentric rings. Error: Invalid geometry detected. Edges overlap or intersect at non-end points.

Question

Alexander 2016-6-27

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/292440-solving-pde-for-geometry-with-concentric-rings-error-invalid-geometry-detected-edges-overlap-or-i

回答： Alan Weiss 2017-6-28

Here is my code which defines a geometry of 6 concentric rings:

function rings_6x_1
model = createpde(1);
d1 = 6.2e-3;
d2 = 8.2e-3;
d3 = 8.3e-3;
d4 = 13.2e-3;
d5 = 13.4e-3;
d6 = 15.0e-3;
% Create 6 circles
C1 = [1 0 0 d1/2]';
C2 = [1 0 0 d2/2]';
C3 = [1 0 0 d3/2]';
C4 = [1 0 0 d4/2]';
C5 = [1 0 0 d5/2]';
C6 = [1 0 0 d6/2]';
% Combine the shapes into one matrix
gd = [C1,C2,C3,C4,C5,C6];
% Give names for the three shapes
ns = char('C1','C2','C3','C4','C5','C6');
ns = ns';
% Specify the concentric rings geometry
sf = 'C1+(C2-C1)+(C3-C2)+(C4-C3)+(C5-C4)+(C6-C5)';
% combines the basic shapes using the set formula
%[dl,bt] = decsg(gd,sf,ns); 
g = decsg(gd,sf,ns);
% View the geometry
figure;
geometryFromEdges(model,g);
pdegplot(model,'EdgeLabels','on')
xlim([-d6,d6])
axis equal
hmax = .1; % element size
msh = generateMesh(model,'Hmax',hmax);
figure;
pdeplot(model);
end

The mesh generator produces the following error:

Error using rings_6x_1 (line 39)
Invalid geometry detected. Edges overlap or intersect at non-end points.

Am I doing something wrong or this is a bug? how can I go around?

2 个评论
显示无隐藏无

Alan Weiss 2016-6-27

Please mark your code sections with the {} Code button to help us read it more easily.

Alan Weiss

MATLAB mathematical toolbox documentation

John D'Errico 2016-6-27

Please learn to use the "{} Code" button to designate code. I've done that for you here, once.

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Ma Yalin 2016-8-11

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/292440-solving-pde-for-geometry-with-concentric-rings-error-invalid-geometry-detected-edges-overlap-or-i#answer_231467

i have the same problem have no idea how to solve it......

1 个评论
显示 -1更早的评论隐藏 -1更早的评论

antoine jury 2017-6-28

pde_ring_solved.m

From the gui it's possible if this script can help someone

请先登录，再进行评论。

Answer 2

Alan Weiss 2017-6-28

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/292440-solving-pde-for-geometry-with-concentric-rings-error-invalid-geometry-detected-edges-overlap-or-i#answer_272269

I believe that this answer will fix your problems. Sorry, I do believe that this is likely a bug.

Alan Weiss

MATLAB mathematical toolbox documentation

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

请先登录，再进行评论。