!   TITLE:  ang_diff.mac (CALCULATION)
!
!
!   OBJECTIVE:
!
!   This sub-macro calculates the subtended angle between 2 angular dimensions,
!   angle#1 and angle#2, as measured from angle#1 to angle#2 in a CLOCKWISE
!   direction.
!
!
!   COMMAND SYNTAX:
!
!           ANG_DIFF, angle#1, angle#2
!
!
!   DESCRIPTION:
!
!   The convention used here is:
!
!           d_angle = angle#1 - angle#2
!
!   The difference between the two angles may then be used to aid in
!   a loop of VROTAT functions. In this case, the angle inputs may be from
!   the storage array ANG_ARRAY.MAC. It may be used for stand-alone command
!   entries as well.
!
!
!
*get,prkey_,active,0,prkey
/nopr
!
ang1_=arg1
ang2_=arg2
!
delta_=ang2_-ang1_
!
*if,delta_,lt,0,then
    d_angle=abs(delta_)
*else
    d_angle=360-delta_
*endif
!
*set,ang1_,
*set,ang2_,
*set,delta_,
!
*if,prkey_,eq,1,then
    /go
*endif