Subroutine: IRCO_PLATE
Purpose: construct a plate coordinate system
Category WORLD COORDINATES, IRAS
File: irco.shl
Author: Do Kester
Person resp.: Do Kester
Address: guspace!do or rugfx4!do (uucp)
Use: call irco_plate(
refcoor I integer
center I doubleprecision array(2)
name I character*(*)
newcoor I/O integer )
refcoor reference coordinate system
center longitude and latitude of the plate
name of the new system
newcoor input: 0 => output: free coordinate number
otherwise output = input
Description:
A plate coordinate system will be created, defined with
respect to REFCOOR. Two angles are necessary to
define the new system: the longitude and the latitude
of the plate with respect to the reference system.
The angles are given in radians. The plate system will
be aligned north-south along the meridian of the reference
system running through the center of the plate.
The central point of the plate has vector (1,0,0).
It is not allowed for NEWCOOR to be the same as REFCOOR.
If NEWCOOR is 0 upon entry, a free coordinate number will
be returned, or 0 if none is available any more.
Upon output NEWCOOR contains the number of the new system.
The connection to coordinate system nr 1 is always made, so that
all connections with other systems will be present in one or
two steps.
Externals:
Updates: 5 May 1990 DK, documentation only
17 DEC 1990 DK, make always connection with system nr 1