#include "erfa.h" void eraC2tcio(double rc2i[3][3], double era, double rpom[3][3], double rc2t[3][3]) /* ** - - - - - - - - - - ** e r a C 2 t c i o ** - - - - - - - - - - ** ** Assemble the celestial to terrestrial matrix from CIO-based ** components (the celestial-to-intermediate matrix, the Earth Rotation ** Angle and the polar motion matrix). ** ** Given: ** rc2i double[3][3] celestial-to-intermediate matrix ** era double Earth rotation angle (radians) ** rpom double[3][3] polar-motion matrix ** ** Returned: ** rc2t double[3][3] celestial-to-terrestrial matrix ** ** Notes: ** ** 1) This function constructs the rotation matrix that transforms ** vectors in the celestial system into vectors in the terrestrial ** system. It does so starting from precomputed components, namely ** the matrix which rotates from celestial coordinates to the ** intermediate frame, the Earth rotation angle and the polar motion ** matrix. One use of the present function is when generating a ** series of celestial-to-terrestrial matrices where only the Earth ** Rotation Angle changes, avoiding the considerable overhead of ** recomputing the precession-nutation more often than necessary to ** achieve given accuracy objectives. ** ** 2) The relationship between the arguments is as follows: ** ** [TRS] = RPOM * R_3(ERA) * rc2i * [CRS] ** ** = rc2t * [CRS] ** ** where [CRS] is a vector in the Geocentric Celestial Reference ** System and [TRS] is a vector in the International Terrestrial ** Reference System (see IERS Conventions 2003). ** ** Called: ** eraCr copy r-matrix ** eraRz rotate around Z-axis ** eraRxr product of two r-matrices ** ** Reference: ** ** McCarthy, D. D., Petit, G. (eds.), 2004, IERS Conventions (2003), ** IERS Technical Note No. 32, BKG ** ** Copyright (C) 2013-2017, NumFOCUS Foundation. ** Derived, with permission, from the SOFA library. See notes at end of file. */ { double r[3][3]; /* Construct the matrix. */ eraCr(rc2i, r); eraRz(era, r); eraRxr(rpom, r, rc2t); return; } /*---------------------------------------------------------------------- ** ** ** Copyright (C) 2013-2017, 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. ** */