Syntax
where are the names of elements or bases.
We use the XGRID: command to remove node and arc definitions.
All nodes associated with the named elements and
bases, and any arcs connecting them to any other arcs, are removed. The
XBASE: and XELEMENT: commands will also remove any arc
and node definitions for the quantities to be deleted. Note that if a
node has been associated with a base then the node remains defined
whilst the base remains defined, whatever the contents of the base.
See §6.2 for
details of specifying collections for the definition part.