SUBROUTINE SANG ( )
Description
THIS ROUTINE RESTRICTS THE PRELIMINARY CALCULATIONS 
RESTRICT ANGLE SCAN BY DISTANCE, BUT IF USER INSISTS ON HIGHER 
ANGLES THAN REASONABLE CHECK AMIND.
Source file:sang.f
Intrinsic Functions Called
INTEGER            MIN0
Local Variables (+ indicates altered content)
INTEGER           +IA,        +IANG,      +ID,        +NANGX(8)
Referenced Common Block Variables (+ indicates altered content)
DON                REAL               AMIND,     GCDKM
RAYS               INTEGER           +NANG
RAYS               REAL               ANG(40)