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+#include "erfa.h"
+
+void eraA2tf(int ndp, double angle, char *sign, int ihmsf[4])
+/*
+** - - - - - - - -
+** e r a A 2 t f
+** - - - - - - - -
+**
+** Decompose radians into hours, minutes, seconds, fraction.
+**
+** Given:
+** ndp int resolution (Note 1)
+** angle double angle in radians
+**
+** Returned:
+** sign char '+' or '-'
+** ihmsf int[4] hours, minutes, seconds, fraction
+**
+** Called:
+** eraD2tf decompose days to hms
+**
+** Notes:
+**
+** 1) The argument ndp is interpreted as follows:
+**
+** ndp resolution
+** : ...0000 00 00
+** -7 1000 00 00
+** -6 100 00 00
+** -5 10 00 00
+** -4 1 00 00
+** -3 0 10 00
+** -2 0 01 00
+** -1 0 00 10
+** 0 0 00 01
+** 1 0 00 00.1
+** 2 0 00 00.01
+** 3 0 00 00.001
+** : 0 00 00.000...
+**
+** 2) The largest positive useful value for ndp is determined by the
+** size of angle, the format of doubles on the target platform, and
+** the risk of overflowing ihmsf[3]. On a typical platform, for
+** angle up to 2pi, the available floating-point precision might
+** correspond to ndp=12. However, the practical limit is typically
+** ndp=9, set by the capacity of a 32-bit int, or ndp=4 if int is
+** only 16 bits.
+**
+** 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[0]=24 and setting ihmsf[0-3] to zero.
+**
+** Copyright (C) 2013-2016, NumFOCUS Foundation.
+** Derived, with permission, from the SOFA library. See notes at end of file.
+*/
+{
+/* Scale then use days to h,m,s function. */
+ eraD2tf(ndp, angle/ERFA_D2PI, sign, ihmsf);
+
+ return;
+
+}
+/*----------------------------------------------------------------------
+**
+**
+** Copyright (C) 2013-2016, NumFOCUS Foundation.
+** All rights reserved.
+**
+** This library is derived, with permission, from the International
+** Astronomical Union's "Standards of Fundamental Astronomy" library,
+** available from http://www.iausofa.org.
+**
+** The ERFA version is intended to retain identical functionality to
+** the SOFA library, but made distinct through different function and
+** file names, as set out in the SOFA license conditions. The SOFA
+** original has a role as a reference standard for the IAU and IERS,
+** and consequently redistribution is permitted only in its unaltered
+** state. The ERFA version is not subject to this restriction and
+** therefore can be included in distributions which do not support the
+** concept of "read only" software.
+**
+** Although the intent is to replicate the SOFA API (other than
+** replacement of prefix names) and results (with the exception of
+** bugs; any that are discovered will be fixed), SOFA is not
+** responsible for any errors found in this version of the library.
+**
+** If you wish to acknowledge the SOFA heritage, please acknowledge
+** that you are using a library derived from SOFA, rather than SOFA
+** itself.
+**
+**
+** TERMS AND CONDITIONS
+**
+** Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions
+** are met:
+**
+** 1 Redistributions of source code must retain the above copyright
+** notice, this list of conditions and the following disclaimer.
+**
+** 2 Redistributions in binary form must reproduce the above copyright
+** notice, this list of conditions and the following disclaimer in
+** the documentation and/or other materials provided with the
+** distribution.
+**
+** 3 Neither the name of the Standards Of Fundamental Astronomy Board,
+** the International Astronomical Union nor the names of its
+** contributors may be used to endorse or promote products derived
+** from this software without specific prior written permission.
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+** FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+** COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+** INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+** BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+** LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+** CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+** ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+** POSSIBILITY OF SUCH DAMAGE.
+**
+*/