The Join command joins all selected compatible grid or database entities together into one entity. If selected entities belong to groups, the entity resulting from the join will become a member of all groups the original unjoined entities belong to. This command is implemented immediately without any command panel appearing.


Tip: After joining two unstructured domains using the Join command, you may notice that the edges of several triangles create a line exactly where the shared connectors used to be. This can be fixed by selecting the domain and clicking on Initialize in the toolbar. The triangles will then be repopulated across the joined domain.

There are a few restrictions on joining entities, as seen on the connector level above.

Select the entities to be joined, then Edit, Join. All currently selected entities of the same type are joined unless doing so would destroy topology. A mixed set of entity types can be selected and each type of the set will be joined into as few entities as possible. Note that selecting domains for joining will not automatically join their connectors, unless the connectors are selected as well.

Three basic situations are shown in the figure above for connectors in which joining would destroy topology:

  • When more than two connectors share a node
  • When there is a gap between connector nodes
  • When more than two connectors share a node (in the form of duplicate connectors)

These same rules can be extended to the joining of domains and blocks. Also note that a dimensioned connector cannot be joined with another one that is not dimensioned.

A successful join of structured domains or blocks will create a new subgrid for each of the original domains or blocks. It will also maintain the existing subgrids before the join if any.