b := gp.isgroup(gp,s<,slot>)

Check if the group s is associated with the zone gridpoint and return true if a match is found in any slot. The check for s will only occur in slot, if provided. Note that this function will return a match if any zone or zone face connected to the gridpoint contains that group name, as well as the gridpoint itself.

A group index or slot index may be used for the arguments s or slot, respectively. Indices operate more efficiently than strings*.


b - true if the group was found for that zone gridpoint


gp - zone gridpoint pointer

s - the group name or index*

slot - the slot name or index*; the check occurs on all slots assigned to the zone if omitted


*Use the group.find and group.find.slot intrinsics to obtain group and slot indices, respectively, and for further information.

Use of the group logic is described in Groups.