[Gmsh] ** On entry to DGESVD parameter number 6 had an illegal value

[David Colignon]

Hi Adam,

yes, it is a tolerance problem and points which are too close are automatically merged.
You can modify the tolerance on the command line with:

gmsh Naca.geo -tol 1e-9

or add in you .geo file:

Geometry.Tolerance = 1e-9 ;


You could also use a fixed number of points and join them with splines.
I attach one example, and there are others examples on the mailing-list:

http://www.geuz.org/pipermail/gmsh/2009/004661.html

http://www.geuz.org/pipermail/gmsh/2009/004532.html

Cheers,

Dave


-- 
David Colignon, Ph.D.
Collaborateur Logistique du F.R.S.-FNRS
CÉCI - Consortium des Équipements de Calcul Intensif
ACE - Applied & Computational Electromagnetics
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Université de Liège
4000 Liège - BELGIQUE
Tél: +32 (0)4 366 37 32
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Adam Larat wrote:
> Hi everyone,
> 
> first, because this is my first message here, thank you for developing 
> this free software, it is very helpful for me.
> Second I'm actually trying to build a mesh for an naca6412 airfoil and I 
> have trouble with it. I have written the script attached and it works 
> well when I ask for a relatively small number of points on the airfoil 
> (for example NACA4_npts = 100;).
> But when I ask for a larger value of this variable (NACA4_npts = 500;), 
> I get the following error :
> 
> alarat at troll:~/Maillages/Naca_Eolienne$ gmsh-2.4.2 Naca.geo  
> -0             Info    : Running 'gmsh-2.4.2 Naca.geo -0'
> Info    : Started on Sun Oct 18 22:42:55 2009
> Info    : Reading 'Naca.geo'
> Error   : Unknown curve -2000
> Info    : Adding edge points to compute mean plane of face 2007
> ** On entry to DGESVD parameter number  6 had an illegal value
> 
> Could someone help me please with this, I have googled it many different 
> ways and didn't get any relevant answer ? Is it a problem of distance 
> between the two nearest points ?
> Thank You,
> 
> Adam
> 
> 
> 
> 
> ------------------------------------------------------------------------
> 
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