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+.help deuler Jun99 "Slalib Package"
+.nf
+
+      SUBROUTINE slDEUL (ORDER, PHI, THETA, PSI, RMAT)
+
+     - - - - - - -
+      D E U L
+     - - - - - - -
+
+  Form a rotation matrix from the Euler angles - three successive
+  rotations about specified Cartesian axes (double precision)
+
+  Given:
+    ORDER   c*(*)   specifies about which axes the rotations occur
+    PHI     d       1st rotation (radians)
+    THETA   d       2nd rotation (   "   )
+    PSI     d       3rd rotation (   "   )
+
+  Returned:
+    RMAT    d(3,3)  rotation matrix
+
+  A rotation is positive when the reference frame rotates
+  anticlockwise as seen looking towards the origin from the
+  positive region of the specified axis.
+
+  The characters of ORDER define which axes the three successive
+  rotations are about.  A typical value is 'ZXZ', indicating that
+  RMAT is to become the direction cosine matrix corresponding to
+  rotations of the reference frame through PHI radians about the
+  old Z-axis, followed by THETA radians about the resulting X-axis,
+  then PSI radians about the resulting Z-axis.
+
+  The axis names can be any of the following, in any order or
+  combination:  X, Y, Z, uppercase or lowercase, 1, 2, 3.  Normal
+  axis labeling/numbering conventions apply;  the xyz (=123)
+  triad is right-handed.  Thus, the 'ZXZ' example given above
+  could be written 'zxz' or '313' (or even 'ZxZ' or '3xZ').  ORDER
+  is terminated by length or by the first unrecognized character.
+
+  Fewer than three rotations are acceptable, in which case the later
+  angle arguments are ignored.  If all rotations are zero, the
+  identity matrix is produced.
+
+  P.T.Wallace   Starlink   23 May 1997
+
+  Copyright (C) 1997 Rutherford Appleton Laboratory
+  Copyright (C) 1995 Association of Universities for Research in Astronomy Inc.
+
+.fi
+.endhelp