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+#include "erfa.h"
+
+void eraAticq(double ri, double di, eraASTROM *astrom,
+ double *rc, double *dc)
+/*
+** - - - - - - - - -
+** e r a A t i c q
+** - - - - - - - - -
+**
+** Quick CIRS RA,Dec to ICRS astrometric place, given the star-
+** independent astrometry parameters.
+**
+** Use of this function is appropriate when efficiency is important and
+** where many star positions are all to be transformed for one date.
+** The star-independent astrometry parameters can be obtained by
+** calling one of the functions eraApci[13], eraApcg[13], eraApco[13]
+** or eraApcs[13].
+**
+** Given:
+** ri,di double CIRS RA,Dec (radians)
+** astrom eraASTROM* star-independent astrometry parameters:
+** pmt double PM time interval (SSB, Julian years)
+** eb double[3] SSB to observer (vector, au)
+** eh double[3] Sun to observer (unit vector)
+** em double distance from Sun to observer (au)
+** v double[3] barycentric observer velocity (vector, c)
+** bm1 double sqrt(1-|v|^2): reciprocal of Lorenz factor
+** bpn double[3][3] bias-precession-nutation matrix
+** along double longitude + s' (radians)
+** xpl double polar motion xp wrt local meridian (radians)
+** ypl double polar motion yp wrt local meridian (radians)
+** sphi double sine of geodetic latitude
+** cphi double cosine of geodetic latitude
+** diurab double magnitude of diurnal aberration vector
+** eral double "local" Earth rotation angle (radians)
+** refa double refraction constant A (radians)
+** refb double refraction constant B (radians)
+**
+** Returned:
+** rc,dc double ICRS astrometric RA,Dec (radians)
+**
+** Notes:
+**
+** 1) Only the Sun is taken into account in the light deflection
+** correction.
+**
+** 2) Iterative techniques are used for the aberration and light
+** deflection corrections so that the functions eraAtic13 (or
+** eraAticq) and eraAtci13 (or eraAtciq) are accurate inverses;
+** even at the edge of the Sun's disk the discrepancy is only about
+** 1 nanoarcsecond.
+**
+** Called:
+** eraS2c spherical coordinates to unit vector
+** eraTrxp product of transpose of r-matrix and p-vector
+** eraZp zero p-vector
+** eraAb stellar aberration
+** eraLdsun light deflection by the Sun
+** eraC2s p-vector to spherical
+** eraAnp normalize angle into range +/- pi
+**
+** Copyright (C) 2013-2016, NumFOCUS Foundation.
+** Derived, with permission, from the SOFA library. See notes at end of file.
+*/
+{
+ int j, i;
+ double pi[3], ppr[3], pnat[3], pco[3], w, d[3], before[3], r2, r,
+ after[3];
+
+
+/* CIRS RA,Dec to Cartesian. */
+ eraS2c(ri, di, pi);
+
+/* Bias-precession-nutation, giving GCRS proper direction. */
+ eraTrxp(astrom->bpn, pi, ppr);
+
+/* Aberration, giving GCRS natural direction. */
+ eraZp(d);
+ for (j = 0; j < 2; j++) {
+ r2 = 0.0;
+ for (i = 0; i < 3; i++) {
+ w = ppr[i] - d[i];
+ before[i] = w;
+ r2 += w*w;
+ }
+ r = sqrt(r2);
+ for (i = 0; i < 3; i++) {
+ before[i] /= r;
+ }
+ eraAb(before, astrom->v, astrom->em, astrom->bm1, after);
+ r2 = 0.0;
+ for (i = 0; i < 3; i++) {
+ d[i] = after[i] - before[i];
+ w = ppr[i] - d[i];
+ pnat[i] = w;
+ r2 += w*w;
+ }
+ r = sqrt(r2);
+ for (i = 0; i < 3; i++) {
+ pnat[i] /= r;
+ }
+ }
+
+/* Light deflection by the Sun, giving BCRS coordinate direction. */
+ eraZp(d);
+ for (j = 0; j < 5; j++) {
+ r2 = 0.0;
+ for (i = 0; i < 3; i++) {
+ w = pnat[i] - d[i];
+ before[i] = w;
+ r2 += w*w;
+ }
+ r = sqrt(r2);
+ for (i = 0; i < 3; i++) {
+ before[i] /= r;
+ }
+ eraLdsun(before, astrom->eh, astrom->em, after);
+ r2 = 0.0;
+ for (i = 0; i < 3; i++) {
+ d[i] = after[i] - before[i];
+ w = pnat[i] - d[i];
+ pco[i] = w;
+ r2 += w*w;
+ }
+ r = sqrt(r2);
+ for (i = 0; i < 3; i++) {
+ pco[i] /= r;
+ }
+ }
+
+/* ICRS astrometric RA,Dec. */
+ eraC2s(pco, &w, dc);
+ *rc = eraAnp(w);
+
+/* Finished. */
+
+}
+/*----------------------------------------------------------------------
+**
+**
+** 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.
+**
+*/