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authorJoseph Hunkeler <jhunkeler@gmail.com>2015-03-04 21:21:30 -0500
committerJoseph Hunkeler <jhunkeler@gmail.com>2015-03-04 21:21:30 -0500
commitd54fe7c1f704a63824c5bfa0ece65245572e9b27 (patch)
treeafc52015ffc2c74e0266653eecef1c8ef8ba5d91 /src/slalib/dr2af.f
downloadcalfuse-d54fe7c1f704a63824c5bfa0ece65245572e9b27.tar.gz
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+ SUBROUTINE sla_DR2AF (NDP, ANGLE, SIGN, IDMSF)
+*+
+* - - - - - -
+* D R 2 A F
+* - - - - - -
+*
+* Convert an angle in radians to degrees, arcminutes, arcseconds
+* (double precision)
+*
+* Given:
+* NDP i number of decimal places of arcseconds
+* ANGLE d angle in radians
+*
+* Returned:
+* SIGN c '+' or '-'
+* IDMSF i(4) degrees, arcminutes, arcseconds, fraction
+*
+* Notes:
+*
+* 1) NDP less than zero is interpreted as zero.
+*
+* 2) The largest useful value for NDP is determined by the size
+* of ANGLE, the format of DOUBLE PRECISION floating-point
+* numbers on the target machine, and the risk of overflowing
+* IDMSF(4). For example, on the VAX, for ANGLE up to 2pi, the
+* available floating-point precision corresponds roughly to
+* NDP=12. However, the practical limit is NDP=9, set by the
+* capacity of the 32-bit integer IDMSF(4).
+*
+* 3) The absolute value of ANGLE may exceed 2pi. In cases where it
+* does not, it is up to the caller to test for and handle the
+* case where ANGLE is very nearly 2pi and rounds up to 360 deg,
+* by testing for IDMSF(1)=360 and setting IDMSF(1-4) to zero.
+*
+* Called: sla_DD2TF
+*
+* P.T.Wallace Starlink 19 March 1999
+*
+* Copyright (C) 1995 Rutherford Appleton Laboratory
+*-
+
+ IMPLICIT NONE
+
+ INTEGER NDP
+ DOUBLE PRECISION ANGLE
+ CHARACTER SIGN*(*)
+ INTEGER IDMSF(4)
+
+* Hours to degrees * radians to turns
+ DOUBLE PRECISION F
+ PARAMETER (F=15D0/6.283185307179586476925287D0)
+
+
+
+* Scale then use days to h,m,s routine
+ CALL sla_DD2TF(NDP,ANGLE*F,SIGN,IDMSF)
+
+ END