Initial commit

1 files changed, 53 insertions, 0 deletions

diff --git a/src/slalib/pav.f b/src/slalib/pav.f
new file mode 100644
index 0000000..7eb1c12
--- /dev/null
+++ b/src/slalib/pav.f
@@ -0,0 +1,53 @@
+      REAL FUNCTION sla_PAV ( V1, V2 )
+*+
+*     - - - -
+*      P A V
+*     - - - -
+*
+*  Position angle of one celestial direction with respect to another.
+*
+*  (single precision)
+*
+*  Given:
+*     V1    r(3)    direction cosines of one point
+*     V2    r(3)    direction cosines of the other point
+*
+*  (The coordinate frames correspond to RA,Dec, Long,Lat etc.)
+*
+*  The result is the bearing (position angle), in radians, of point
+*  V2 with respect to point V1.  It is in the range +/- pi.  The
+*  sense is such that if V2 is a small distance east of V1, the
+*  bearing is about +pi/2.  Zero is returned if the two points
+*  are coincident.
+*
+*  V1 and V2 do not have to be unit vectors.
+*
+*  The routine sla_BEAR performs an equivalent function except
+*  that the points are specified in the form of spherical
+*  coordinates.
+*
+*  Called:  sla_DPAV
+*
+*  Patrick Wallace   Starlink   23 May 1997
+*
+*  Copyright (C) 1997 Rutherford Appleton Laboratory
+*-
+
+      IMPLICIT NONE
+
+      REAL V1(3),V2(3)
+
+      INTEGER I
+      DOUBLE PRECISION D1(3),D2(3)
+
+      DOUBLE PRECISION sla_DPAV
+
+
+*  Call the double precision version
+      DO I=1,3
+         D1(I)=V1(I)
+         D2(I)=V2(I)
+      END DO
+      sla_PAV=sla_DPAV(D1,D2)
+
+      END