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.help cr2af Jun99 "Slalib Package"
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SUBROUTINE slCRAF (NDP, ANGLE, SIGN, IDMSF)
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C R A F
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Convert an angle in radians into degrees, arcminutes, arcseconds
(single precision)
Given:
NDP int number of decimal places of arcseconds
ANGLE real angle in radians
Returned:
SIGN char '+' or '-'
IDMSF int(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 REAL 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=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 360 deg,
by testing for IDMSF(1)=360 and setting IDMSF(1-4) to zero.
Called: slCDTF
P.T.Wallace Starlink 18 March 1999
Copyright (C) 1999 Rutherford Appleton Laboratory
Copyright (C) 1995 Association of Universities for Research in Astronomy Inc.
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.endhelp
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