Determines if an element is in a group.
The group handle, returned from the GrpOpen() function. The group handle identifies the table where all data on the associated group is stored.
The element to locate, from 0 to 16375.
1 if the element is in the group, otherwise 0 is returned.
GrpOpen, GrpInsert, GrpDelete
IF GrpIn(hGrp,10) THEN
Prompt("Area 10 in this group");