[Gmsh] Reduce number of digits in key-format file

[Christophe Geuzaine]

> On 20 Mar 2020, at 22:54, Xingsheng Sun <xssun10 at gmail.com> wrote:
> 
> Dear Christophe and Winfried,
> 
> Thank you so much for your help. The problem has been solved.
> 
> The reason is that LS-DYNA can only read 16 digits, while in the output file of Gmsh some numbers have 17 digits. For example, in my previous email 0.012499999999976 has 17 digits including the dot, which cannot be read by LS-DYNA. I also found that the 17-digit numbers only happen when its value is close to zero. Then I moved the entire mesh by 1 in all x-, y- and z-coordinates. Then the output file by Gmsh works well for LS-DYNA.
> 

Can you give the latest dev snapshot a try and let us know if it fixes the problem?

Thanks,

Christophe

> Hope the solution helps the people who might have the same problem.
> 
> Best wishes,
> Xingsheng
> 
> On Fri, Mar 20, 2020 at 4:23 AM Winfried Boxleitner <winfried.boxleitner at ait.ac.at> wrote:
> dear Christophe,
> my awk-script is meant as an example only, howto modify the msh-file
> after creation. for users not familiar to commandline tools however, this
> is not useful. I personally have no problems with the current format.
> remark: until now I only used msh version 2, because this can be used
> together with FreeFem.
> 
> 
> Winfried
> 
> On Fri, 20 Mar 2020, Christophe Geuzaine wrote:
> 
> >
> >
> >> On 20 Mar 2020, at 07:59, Winfried Boxleitner <winfried.boxleitner at ait.ac.at> wrote:
> >>
> >> dear Xingsheng,
> >> if you are used to commandline you can modify my awk-script to fit your needs.
> >>
> >> to format the mesh file use the following command:
> >> awk -f pretty_print_msh.awk input.msh > output.msh
> >>
> >
> > Do you mean that we should use %12.6g in our KEY export?
> >
> > Christophe
> >
> >
> >> the awk-script is attached
> >>
> >> best regards,
> >> Winfried
> >>
> >>
> >> On Thu, 19 Mar 2020, Xingsheng Sun wrote:
> >>
> >>> Hello All,
> >>>
> >>> I am using Gmsh to generate the mesh file for Ls-dyna. The problem is that
> >>> in the key-format file generated by Gmsh, the coordinates of nodes have too
> >>> many digits. For instance, in the node information:
> >>>
> >>> *NODE
> >>> 22, 0, 0.012499999999976, -0.001
> >>> 23, 0, 0.02499999999995, -0.001
> >>> 24, 0, 0.037499999999926, -0.001
> >>> 25, 0, 0.049999999999907, -0.001
> >>>
> >>> the y-coordinates of nodes 22-25 have 15 digits that cannot be read by
> >>> Ls-dyna.
> >>>
> >>> So could any people shed light on how to reduce the number of digits in
> >>> Gmsh? I am using command lines, not GUI. Thank you so much in advance.
> >>>
> >>> Best regards,
> >>> Xingsheng
> >>>
> >>
> >>
> >>  ______________________________________________________________________
> >> /
> >> | Winfried Boxleitner
> >> | Scientist
> >> | AIT Austrian Institute of Technology GmbH
> >> \______________________________________________________________________<pretty_print_msh.awk>_______________________________________________
> >> gmsh mailing list
> >> gmsh at onelab.info
> >> http://onelab.info/mailman/listinfo/gmsh
> >
> > —
> > Prof. Christophe Geuzaine
> > University of Liege, Electrical Engineering and Computer Science
> > http://www.montefiore.ulg.ac.be/~geuzaine
> >
> >
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— 
Prof. Christophe Geuzaine
University of Liege, Electrical Engineering and Computer Science 
http://www.montefiore.ulg.ac.be/~geuzaine