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- ACTION:
- Form the rotation matrix corresponding to a given axial vector
(single precision).
- CALL:
- CALL sla_AV2M (AXVEC, RMAT)
- GIVEN:
-
AXVEC |
R(3) |
axial vector (radians) |
- RETURNED:
-
RMAT |
R(3,3) |
rotation matrix |
- NOTES:
- 1.
- A rotation matrix describes a rotation about some arbitrary axis.
The axis is called the Euler axis, and the angle through which the
reference frame rotates is called the Euler angle. The axial
vector supplied to this routine has the same direction as the
Euler axis, and its magnitude is the Euler angle 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.
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SLALIB --- Positional Astronomy Library
Starlink User Note 67
P. T. Wallace
25 January 2000
E-mail:ptw@star.rl.ac.uk