GP   {id = gpid} x y z

This command creates a single new gridpoint at position x, y, z. If id is specified, then the gridpoint is assigned this ID number, provided this ID number is not already in use by another gridpoint. If id is not specified, then the gridpoint is assigned the next available gridpoint ID number. Also see the ZONE command.

ZONE   {id = zid} {brick wedge pyramid dbrick tetra} {id = gpid or x y z}

This command creates a single new zone of the specified type using existing gridpoints. (For example, if gridpoints with IDs of 1 through 8 exist, then the command

      zone id = 21 brick id 1 id 2 id 3 id 4 id 5 id 6 id 7 id 8

would create a new brick-type zone with an ID of 21.

If the zone ID (zid) parameter is missing, then the new zone is given the next available zone number. For example,

      zone brick id 1 id 2 id 3 id 4 id 5 id 6 id 7 id 8

See the figure in Orientation of Nodes and Zones for the zone geometry specifications. brick is the default zone type.

Instead of specifying the gridpoint ID, the x, y, z coordinates of the gridpoint can be specified. The gridpoint nearest to the specified x, y, z will be used. Any combination of coordinates and gridpoint IDs can be used with this command. For example,

      zone id 72 tetra id 5 3.45 1.02 7.04 id 7 2.10 8.03 4.07

The preceding command specifies a tetra zone with two gridpoint IDs and two pairs of gridpoint x y z coordinates.