// Copyright (c) CNES 2008 // // This software is part of CelestLab, a CNES toolbox for Scilab // // This software is governed by the CeCILL license under French law and // abiding by the rules of distribution of free software. You can use, // modify and/ or redistribute the software under the terms of the CeCILL // license as circulated by CEA, CNRS and INRIA at the following URL // 'http://www.cecill.info'. function [pos_ter,vel_ter,jacob] = CL_fr_J20002ter(cjd,pos_J2000, vel_J2000,ut1_utc,xp,yp,dPsi,dEps,conv_iers) // EME2000 (J2000) to terrestrial frame vector transformation - DEPRECATED // // Calling Sequence // [pos_ter,vel_ter,jacob] = CL_fr_J20002ter(cjd,pos_J2000 [,vel_J2000,ut1_utc,xp,yp,dPsi,dEps,conv_iers]) // // Description // //

This function is deprecated.

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Replacement function: CL_fr_convert

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Converts position and (optionally) velocity vectors from EME2000 to the // terrestrial ("Earth fixed") reference frame.

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The jacobian of the transformation is optionally computed.

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See Reference frames for more details on the definition of reference frames.

// // // // Parameters // cjd: modified julian day from 1950.0 (UTC) (1xN or 1x1) // pos_J2000: position vector relative to EME2000 [m] (3xN or 3x1) // vel_J2000: (optional) velocity vector relative to EME2000 [m/s] (3xN or 3x1) // ut1_utc : (optional) ut1-utc [seconds] (default is 0) (1xN or 1x1) // xp : (optional) x polar coordinate [radians] (default is 0) (1xN or 1x1) // yp : (optional) y polar coordinate [radians] (default is 0) (1xN or 1x1) // dPsi : (optional) Nutation corrections [radians] (default is 0) (1xN or 1x1) // dEps : (optional) Nutation corrections [radians] (default is 0) (1xN or 1x1) // conv_iers : (optional) Convention IERS. Only iers 1996 (Lieske/Wahr) is implemented (default is "iers_1996") // pos_ter: position vector relative to terrestrial frame [m] (3xN) // vel_ter: (optional) velocity vector relative to terrestrial frame [m/s] (3xN) // jacob: (optional) jacobian of the transformation (6x6xN) // // Authors // CNES - DCT/SB // // Bibliography // 1) IERS Conventions (1996), Dennis D. McCarthy // 2) Explanatory Supplement to the Astronomical Almanac, Seidelman (1992) // // See also // CL_fr_ter2J2000Mat // CL_fr_J20002ter // // Examples // // Position // pos_J2000 = [7000.e3; 0; 0]; // cjd = [21010 , 21011]; // pos_ter = CL_fr_J20002ter(cjd, pos_J2000); // // // Position, velocity and jacobian // pos_J2000 = [7000.e3; 0; 0]; // vel_J2000 = [0; 7000; 0]; // cjd = [21010 , 21011]; // [pos_ter, vel_ter, jacob] = CL_fr_J20002ter(cjd, [pos_J2000,pos_J2000], [vel_J2000,vel_J2000]) // Declarations: // Code: CL__warnDeprecated(); // deprecated function vel_present = %t; if (~exists('vel_J2000','local')); vel_J2000 = []; vel_present = %f; end if (~exists('ut1_utc','local')); ut1_utc = zeros(cjd); end if (~exists('xp','local')); xp = zeros(cjd); end if (~exists('yp','local')); yp = zeros(cjd); end if (~exists('dPsi','local')); dPsi = zeros(cjd); end if (~exists('dEps','local')); dEps = zeros(cjd); end if (~exists('conv_iers','local')); conv_iers = "iers_1996"; end if (conv_iers <> "iers_1996") then CL__error("Only iers_1996 model is implemented"); end vel_ter = []; jacob = []; compute_vel = %f; compute_jac = %f; if (argn(1) == 1) flag = "n"; // means that only the matrix will be computed end if (argn(1) >= 2) compute_vel = %t; flag = "p"; // means that the matrix and angular velocity vectors will be computed end if (argn(1) >= 3) compute_jac = %t; end if (compute_vel & ~vel_present) CL__error("Input velocity missing"); end // Check argument sizes, and resize if necessary: if (vel_present) [cjd,pos_J2000,vel_J2000,ut1_utc,xp,yp,dPsi,dEps] = CL__checkInputs(cjd,1, pos_J2000,3, vel_J2000,3, ut1_utc,1, xp,1, yp,1, dPsi,1, dEps,1 ); else [cjd,pos_J2000,ut1_utc,xp,yp,dPsi,dEps] = CL__checkInputs(cjd,1, pos_J2000,3, ut1_utc,1, xp,1, yp,1, dPsi,1, dEps,1 ); end // pole - associated angular velocity = 0 W = CL_mod_polarMotionMatrix(xp,yp); //Conversion TUC --> TAI [cjdtai]=CL_dat_utc2tai(cjd); jj_tai = floor(cjdtai); sec_tai = (cjdtai-jj_tai)*86400.0; cjdut1 = cjd + ut1_utc/86400.0; [TempsSideralMoyen,TSMP] = CL_mod_sidTime(cjdut1); [eps0,eps0p] = CL_mod_meanObliquity(jj_tai,sec_tai,flag); [NUT,F,NUTP,FP] = CL_mod_nutationAngles(jj_tai,sec_tai,flag); [equi,equip] = CL_mod_equinoxesEquation(NUT(1,:),eps0,F(5,:),NUTP(1,:),eps0p,FP(5,:)); TempsSideralVrai = TempsSideralMoyen+equi; R = CL_rot_angles2matrix(3,-TempsSideralVrai); // angular rotation vector that corresponds to R matrix // same conventions as for other angles OM_rot = [zeros(TempsSideralVrai); zeros(TempsSideralVrai); -(equip+TSMP).*ones(TempsSideralVrai)]; NUT = NUT+[dPsi;dEps]; [N,OM_nut] = CL_mod_nutationMatrix([eps0; NUT;],[eps0p ; NUTP],[],flag); [K,KP,KPP] = CL_mod_precessionAngles(jj_tai,sec_tai,flag); [PREC,OM_prec] = CL_mod_precessionMatrix(K,KP,KPP,flag); // NOTE: // // frames: ter --> Fa --> Fb --> Fc --> J2000 // mat: W R N PREC // omega: 0 OM_rot OM_nut OM_prec // // omega: ang velocity F2/F1 with coordinates in F2 with: // X_F2 = mat * X_F1 // example: // X_J2000 = PREC * X_Fc // OM_prec = omega J2000/Fc with coordinates in J2000 // NOTE: omega in CL_rot_pvConvert call: // final/initial, coordinates in initial frame // Precession (PREC) // OM_prec = omega J2000/Fc (coord in J2000) // PREC = transf matrix Fc->J2000 <=> X_J2000 = PREC * X_Fc [pos_tmp, vel_tmp, jacob] = CL_rot_pvConvert(pos_J2000, vel_J2000, PREC', -OM_prec, ... cvel=compute_vel, cjac=compute_jac); // Nutation (N) // OM_nut = omega Fc/Fb (coord in Fc) // N = transf matrix Fb->Fc <=> X_Fc = N * X_Fb [pos_tmp, vel_tmp, jacob_tmp] = CL_rot_pvConvert(pos_tmp, vel_tmp, N', -OM_nut, ... cvel=compute_vel, cjac=compute_jac); jacob = jacob_tmp * jacob; // Earth rotation (R*W) // OM_rot = omega Fb/ter (coord in Fb) // R*W = transf matrix ter->Fb <=> X_Fb = (R*W) * X_ter [pos_ter, vel_ter, jacob_tmp] = CL_rot_pvConvert(pos_tmp, vel_tmp, (R*W)', -OM_rot, ... cvel=compute_vel, cjac=compute_jac); jacob = jacob_tmp * jacob; endfunction