next up previous 269
Next: SLA_DBEAR - Direction Between Points on a Sphere
Up: SUBPROGRAM SPECIFICATIONS
Previous: SLA_DAT - TAIUTC


SLA_DAV2M - Rotation Matrix from Axial Vector

ACTION:
Form the rotation matrix corresponding to a given axial vector (double precision).
CALL:
CALL sla_DAV2M (AXVEC, RMAT)
GIVEN:

AXVEC D(3) axial vector (radians)
RETURNED:

RMAT D(3,3) rotation matrix
NOTES:
  1. A rotation matrix describes a rotation about some arbitrary axis, called the Euler axis. The axial vector supplied to this routine has the same direction as the Euler axis, and its magnitude is the amount of rotation in radians.
  2. If AXVEC is null, the unit matrix is returned.
  3. The reference frame rotates clockwise as seen looking along the axial vector from the origin.


next up previous 269
Next: SLA_DBEAR - Direction Between Points on a Sphere
Up: SUBPROGRAM SPECIFICATIONS
Previous: SLA_DAT - TAIUTC

SLALIB --- Positional Astronomy Library
Starlink User Note 67
P. T. Wallace
19 December 2005
E-mail:ussc@star.rl.ac.uk

Copyright © 2010 Science and Technology Facilities Council