SUBROUTINE iau_FW2M ( GAMB, PHIB, PSI, EPS, R ) *+ * - - - - - - - - - * i a u _ F W 2 M * - - - - - - - - - * * Form rotation matrix given the Fukushima-Williams angles. * * This routine is part of the International Astronomical Union's * SOFA (Standards of Fundamental Astronomy) software collection. * * Status: support routine. * * Given: * GAMB d F-W angle gamma_bar (radians) * PHIB d F-W angle phi_bar (radians) * PSI d F-W angle psi (radians) * EPS d F-W angle epsilon (radians) * * Returned: * R d(3,3) rotation matrix * * Notes: * * 1) Naming the following points: * * e = J2000 ecliptic pole, * p = GCRS pole, * E = ecliptic pole of date, * and P = CIP, * * the four Fukushima-Williams angles are as follows: * * GAMB = gamma = epE * PHIB = phi = pE * PSI = psi = pEP * EPS = epsilon = EP * * 2) The matrix representing the combined effects of frame bias, * precession and nutation is: * * NxPxB = R_1(-EPS).R_3(-PSI).R_1(PHIB).R_3(GAMB) * * 3) Three different matrices can be constructed, depending on the * supplied angles: * * o To obtain the nutation x precession x frame bias matrix, * generate the four precession angles, generate the nutation * components and add them to the psi_bar and epsilon_A angles, * and call the present routine. * * o To obtain the precession x frame bias matrix, generate the * four precession angles and call the present routine. * * o To obtain the frame bias matrix, generate the four precession * angles for date J2000.0 and call the present routine. * * The nutation-only and precession-only matrices can if necessary * be obtained by combining these three appropriately. * * Called: * iau_IR initialize r-matrix to identity * iau_RZ rotate around Z-axis * iau_RX rotate around X-axis * * Reference: * * Hilton, J. et al., 2006, Celest.Mech.Dyn.Astron. 94, 351 * * This revision: 25 October 2006 * * Copyright (C) 2007 IAU SOFA Review Board. See notes at end. * *----------------------------------------------------------------------- IMPLICIT NONE DOUBLE PRECISION GAMB, PHIB, PSI, EPS, R(3,3) * Construct the matrix. CALL iau_IR ( R ) CALL iau_RZ ( GAMB, R ) CALL iau_RX ( PHIB, R ) CALL iau_RZ ( -PSI, R ) CALL iau_RX ( -EPS, R ) * Finished. *+---------------------------------------------------------------------- * * Copyright (C) 2007 * Standards Of Fundamental Astronomy Review Board * of the International Astronomical Union. * * ===================== * SOFA Software License * ===================== * * NOTICE TO USER: * * BY USING THIS SOFTWARE YOU ACCEPT THE FOLLOWING TERMS AND CONDITIONS * WHICH APPLY TO ITS USE. * * 1. The Software is owned by the IAU SOFA Review Board ("the Board"). * * 2. The Software is made available free of charge for use by: * * a) private individuals for non-profit research; and * * b) non-profit educational, academic and research institutions. * * 3. Commercial use of the Software is specifically excluded from the * terms and conditions of this license. Commercial use of the * Software is subject to the prior written agreement of the Board on * terms to be agreed. * * 4. The provision of any version of the Software under the terms and * conditions specified herein does not imply that future versions * will also be made available under the same terms and conditions. * * 5. The user may modify the Software for his/her own purposes. The * user may distribute the modified software provided that the Board * is informed and that a copy of the modified software is made * available to the Board on request. All modifications made by the * user shall be clearly identified to show how the modified software * differs from the original Software, and the name(s) of the * affected routine(s) shall be changed. The original SOFA Software * License text must be present. * * 6. In any published work produced by the user and which includes * results achieved by using the Software, the user shall acknowledge * that the Software was used in producing the information contained * in such publication. * * 7. The user may incorporate or embed the Software into other software * products which he/she may then give away free of charge but not * sell provided the user makes due acknowledgement of the use which * he/she has made of the Software in creating such software * products. Any redistribution of the Software in this way shall be * made under the same terms and conditions under which the user * received it from the SOFA Center. * * 8. The user shall not cause the Software to be brought into * disrepute, either by misuse, or use for inappropriate tasks, or by * inappropriate modification. * * 9. The Software is provided to the user "as is" and the Board makes * no warranty as to its use or performance. The Board does not and * cannot warrant the performance or results which the user may * obtain by using the Software. The Board makes no warranties, * express or implied, as to non-infringement of third party rights, * merchantability, or fitness for any particular purpose. In no * event will the Board be liable to the user for any consequential, * incidental, or special damages, including any lost profits or lost * savings, even if a Board representative has been advised of such * damages, or for any claim by any third party. * * Correspondence concerning SOFA software should be addressed as * follows: * * Internet email: sofa@rl.ac.uk * Postal address: IAU SOFA Center * Rutherford Appleton Laboratory * Chilton, Didcot, Oxon OX11 0QX * United Kingdom * * *----------------------------------------------------------------------- END