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+.help vn Jun99 "Slalib Package"
+.nf
+
+      SUBROUTINE slVN (V, UV, VM)
+
+     - - -
+      V N
+     - - -
+
+  Normalizes a 3-vector also giving the modulus (single precision)
+
+  Given:
+     V       real(3)      vector
+
+  Returned:
+     UV      real(3)      unit vector in direction of V
+     VM      real         modulus of V
+
+  If the modulus of V is zero, UV is set to zero as well
+
+  P.T.Wallace   Starlink   23 November 1995
+
+  Copyright (C) 1995 Rutherford Appleton Laboratory
+  Copyright (C) 1995 Association of Universities for Research in Astronomy Inc.
+
+.fi
+.endhelp