[Gmsh] Joining-Merging(?) 2 msh files

[jlsonnette at tiscali.fr]

Dear Gmsh-users

I am exploring the possibilities in Gmsh to add two geo-files and/or two
msh-files together -- preferably the later.

First, I have developed a mesh for the main branch of a river (2D Mesh for
the Shallow Water Equations), and secondly I have created a mesh for a
sub-branch. (The two files have been created in a consistent coordinate
system.) Now, I would like to put them together to create a more complete
model.

I am not certain that 'Merge' actually would do what I want.  The
explanation on the Merge-function I have found on:
http://www.geuz.org/gmsh/doc/texinfo/gmsh_9.html
is rather promissing, but at the same time it isn't quite what I am
looking for, putting two .msh files together.

Would someone be able to point me in the right direction? (I would be very
grateful.)  It could of course be that I haven't been searching on the
correct keywords, and I would like to apologise in that case.

When I look at the .msh files, I see that each of them starts numbering
the nodes from 1 onwards (what of course is logical).  I wondered
if I wrote a script that changes the numbering of the second files (first
node following the last node number of the last file, and so on), whether
this would by-pass the problem.  However, I fear whether this might have
computational drawbacks -- though I am not certain.


I would like to thank you for your consideration.
Best regards,


Jean