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SUBROUTINE sla_CR2TF (NDP, ANGLE, SIGN, IHMSF)
*+
* - - - - - -
* C R 2 T F
* - - - - - -
*
* Convert an angle in radians into hours, minutes, seconds
* (single precision)
*
* Given:
* NDP int number of decimal places of seconds
* ANGLE real angle in radians
*
* Returned:
* SIGN char '+' or '-'
* IHMSF int(4) hours, minutes, seconds, 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 REAL floating-point numbers on the target
* machine, and the risk of overflowing IHMSF(4). For example,
* on the VAX, for ANGLE up to 2pi, the available floating-point
* precision corresponds roughly to NDP=3. This is well below
* the ultimate limit of NDP=9 set by the capacity of the 32-bit
* integer IHMSF(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 24 hours,
* by testing for IHMSF(1)=24 and setting IHMSF(1-4) to zero.
*
* Called: sla_CD2TF
*
* P.T.Wallace Starlink 18 March 1999
*
* Copyright (C) 1999 Rutherford Appleton Laboratory
*-
IMPLICIT NONE
INTEGER NDP
REAL ANGLE
CHARACTER SIGN*(*)
INTEGER IHMSF(4)
* Turns to radians
REAL T2R
PARAMETER (T2R=6.283185307179586476925287)
* Scale then use days to h,m,s routine
CALL sla_CD2TF(NDP,ANGLE/T2R,SIGN,IHMSF)
END
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