[Gmsh] collocated nodes

[Timur Garipov]

Hi Christophe and Jean-François,
you make great job with gmsh.
I am Timur Garipov and I am working at Stanford. I am developing software for solving geomechanical and mechanical problem. Gmsh create perfect grid but I can not create mesh for special case. May be I am doing something wrong.
I need mesh with collocated nodes.
For example, domain divided by surface A and divide domain for two part C and D. Gmsh generate one set of nodes for subdomains C and D. If I specified two surfaces A1 and A2 and this surfaces has the same coordinates gmsh create different set of nodes. But, node coordinates has different coordinates. Is it possible create collocated nodes and return flag that this nodes are collocated?

Thank you.

p.s. Mesh example
  |  |
 -a  b-
  |  |
 -c  d-
  |  |
 -e  f-
  |  |

(a,b) has a different number but the same coordinates.