[Gmsh] Bug in gmsh 1.63.2

[Christophe Geuzaine]

Clemens Verhoosel wrote:
> Dear Christophe,
> 
> As you requested, my exact sequence of steps. I tried it again myself
> and again the problem occured:
> 
> 1) I make a new geo file.
> 2) I use edit in the geometry menu to get access to the geo file and I
> define the parameters I want to use:
> 
>            lc = 0.1;
>            a   = 1;
>            b   = 2;
> 
>     I then save the geo file and in the menu I click on reload.
> 3) I then use the gmsh geometry menus to define the geometry such that I
> end up with
> 
>            lc = 0.1;
>            a   = 1;
>            b   = 2;
>            Point(1) = {a, 0, 0, lc};
>            Point(2) = {a, 0, 0, lc};
>            Point(3) = {a, b, 0, lc};
>            Point(4) = {0, b, 0, lc};
>            Line (1) = {1, 2};
>            Line (2) = {2, 3};
>            Line (3) = {3, 4};
>            Line (4) = {4, 1};
>            Line Loop (1000006) = {2, 3, 4, 1};
>            Plane Surface (6) = {1000006};
>            Physical Line (7) = {1};
>            Physical Line (8) = {2};
>            Physical Line (9) = {3};
>            Physical Line (10) = {4};
>            Physical Surface (11) = {6};
> 
>  4) I save the geometry file by selecting file->save as.


Clemens - I see: it's not a bug, it's a feature ;-)

When you modify a geometry in the graphical user interface, the
corresponding .geo file is automatically saved: you don't have to save 
it with "File->Save as->Gmsh unrolled geometry".

The purpose of "File->Save as->Gmsh unrolled geometry" is to unroll (or 
"flatten") all the commands in a geo file, and output an "explicit" 
geometry, with no high-level script commands.

So in short, just skip step 4) above and you should be fine.

Cheers,

Christophe


>  5) I go to the meshing part and create a first order triangular mesh.
>  6) I save the mesh using the save button in the mesh menu.
>  7) I then go back to the geometry module and click edit. the result is
> 
>            Point(1) = {0, 0, 0, 0.1};
>            Point(2) = {1, 0, 0, 0.1};
>            Point(3) = {1, 2, 0, 0.1};
>            Point(4) = {0, 2, 0, 0.1};
>            Line (1) = {1, 2};
>            Line (2) = {2, 3};
>            Line (3) = {3, 4};
>            Line (4) = {4, 1};
>            Line Loop (1000006) = {2, 3, 4, 1};
>            Plane Surface (6) = {1000006};
>            Physical Line (7) = {1};
>            Physical Line (8) = {2};
>            Physical Line (9) = {3};
>            Physical Line (10) = {4};
>            Physical Surface (11) = {6};
> 
> 8) Unfortunately the parameters have now been filled in.
> 
> I hope you'll be able to reconstruct this problem. Can you let me know
> if this problem can easily be solved?
> 
> Best regards,
> 
> Clemens Verhoosel
> 
> 
> Christophe Geuzaine wrote:
>> Clemens Verhoosel wrote:
>>> Dear gmsh-developers,
>>>
>>> In gmsh 1..63.2 and earlier versions it sometimes happens that if I
>>> create a .geo file in which I e.g. write
>>>
>>>  lc = 0.1;
>>>  h   =  1;
>>>
>>> and use these parameters to define the points, that after reloading and
>>> reopening the .geo file, the parameters have disappeared and have been
>>> substituted at the places where the parameters were called. Adjusting
>>> sizes and mesh refinement then becomes more complicated (less flexible).
>> That's weird. Could you give us the exact sequence of steps that you
>> follow, so that we can try to reproduce this behavior over here?
>>
>> Thanks,
>>
>> Christophe
>>
>>
>>> Is this a bug in the program or am I doing wrong something myself?
>>> Anyway, could you please help me to fix this problem?
>>>
>>> Best regards,
>>>
>>> Clemens Verhoosel
>>> Ph.D. student at Delft University of Technology the Netherlands
>>> _______________________________________________
>>> gmsh mailing list
>>> 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