# [Gmsh] Issue with if statements and planes

Christophe Geuzaine cgeuzaine at ulg.ac.be
Thu Feb 11 13:37:15 CET 2016

```> On 09 Feb 2016, at 08:08, Jimmie Lahti <jimmie.lahti at malags.se> wrote:
>
> Hello,
>
> I have been trying to solve an issue where I can decide if the 2d plane shall have a hollow structure or not. Please note that I have tried changing numbering  and if I comment any half of the if statement it works. So the issue seems to be the double definition of the Plane.
>
> The error message I get is:
> “””
> Info    : Running 'gmsh -2 hollowbowtie.geo' [Gmsh 2.10.1, 1 node, max. 1 thread]

The "Else" command was only added in Gmsh 2.11...

> Info    : Started on Mon Feb  8 14:47:23 2016
> Error   : 'hollowbowtie.geo', line 118 : syntax error (Plane)
> Info    : Done reading 'hollowbowtie.geo'
> “””
>
> The code:
> “””
> 106 If (hollow_length > 0)
> 107         Circle(9) = {9, 21, 10};
> 108         Circle(10) = {11, 19, 12};
> 109         Circle(11) = {12, 18, 13};
> 110         Circle(12) = {13, 20, 14};
> 111         Line(13) = {9, 14};
> 112         Line(14) = {11, 10};
> 113         Line Loop(16) = {13, -12, -11, -10, 14, -9};
> 114
> 115         Plane Surface(17) = {15, 16};
> 116         Physical Surface(18) = {17};
> 117 Else
> 118         Plane Surface(30) = {15};
> 119         Physical Surface(31) = {30};
> 120 EndIf
> “””
>
>
> Jimmie Lahti
> Electronic engineer
>
> Mobile No number
> Direct +46 953 34 565
> jimmie.lahti at guidelinegeo.com
>
> Guideline Geo AB
> http://www.guidelinegeo.com
> http://www.abem.se
> http://www.malags.se
>
> _______________________________________________
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--
Prof. Christophe Geuzaine
University of Liege, Electrical Engineering and Computer Science
http://www.montefiore.ulg.ac.be/~geuzaine

Tetrahedron V, July 4-5 2016: http://tetrahedron.montefiore.ulg.ac.be
Free software: http://gmsh.info | http://getdp.info | http://onelab.info

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