[Gmsh] line loop

[Christophe Geuzaine]

Ronan GUENANFF wrote:
> hello,
> 
> I am trying to make a line loop with two line arrays
> the union of which constitute a whole line but
> the order of the sublines is not respected in the arrays.
> "Line Loop is wrong"
> What is the symptom of this error?
> 
> I also tried with a unique array where the order is not
> respected either, but it still produces the error.
> 
> Do I have to order my array with continuous sublines?
> 

The sublines do not have to be ordered, but their orientations should be 
consistent. Here is an example:

Point(1) = {0, 0, 0, 1};
Point(2) = {1, 0, 0, 1} ;
Point(3) = {1, 3, 0, 1} ;
Point(4) = {0, 3, 0, 1} ;
Line(1) = {1,2} ;
Line(2) = {3,2} ;
Line(3) = {3,4} ;
Line(4) = {4,1} ;

// ok
aa[] = {4,1,-2,3} ;

// also ok: gmsh will reorder the list automatically
//aa[] = {4,-2,1,3} ;

// not ok: orientations do not match
//aa[] = {4,2,1,3} ;


Line Loop(1) = aa[] ;
Plane Surface(1) = 1;


> Thank you for responding,
> 
> Best regards,
> 
> Ronan Guénanff.
> 
> _______________________________________________
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> gmsh at geuz.org
> http://www.geuz.org/mailman/listinfo/gmsh
> 


-- 
Christophe Geuzaine
Assistant Professor, Case Western Reserve University, Mathematics
http://www.case.edu/artsci/math/geuzaine