1 /* zzspksb1.f -- translated by f2c (version 19980913).
2    You must link the resulting object file with the libraries:
3 	-lf2c -lm   (in that order)
4 */
5 
6 #include "f2c.h"
7 
8 /* $Procedure ZZSPKSB1 ( S/P Kernel, solar system barycenter ) */
zzspksb1_(integer * targ,doublereal * et,char * ref,doublereal * starg,ftnlen ref_len)9 /* Subroutine */ int zzspksb1_(integer *targ, doublereal *et, char *ref,
10 	doublereal *starg, ftnlen ref_len)
11 {
12     integer bary;
13     extern /* Subroutine */ int zzspkgo1_(integer *, doublereal *, char *,
14 	    integer *, doublereal *, doublereal *, ftnlen), chkin_(char *,
15 	    ftnlen);
16     doublereal lt;
17     extern /* Subroutine */ int chkout_(char *, ftnlen);
18     extern logical return_(void);
19 
20 /* $ Abstract */
21 
22 /*     SPICE Private routine intended solely for the support of SPICE */
23 /*     routines.  Users should not call this routine directly due */
24 /*     to the volatile nature of this routine. */
25 
26 /*     Return the state (position and velocity) of a target body */
27 /*     relative to the solar system barycenter. */
28 
29 /* $ Disclaimer */
30 
31 /*     THIS SOFTWARE AND ANY RELATED MATERIALS WERE CREATED BY THE */
32 /*     CALIFORNIA INSTITUTE OF TECHNOLOGY (CALTECH) UNDER A U.S. */
33 /*     GOVERNMENT CONTRACT WITH THE NATIONAL AERONAUTICS AND SPACE */
34 /*     ADMINISTRATION (NASA). THE SOFTWARE IS TECHNOLOGY AND SOFTWARE */
35 /*     PUBLICLY AVAILABLE UNDER U.S. EXPORT LAWS AND IS PROVIDED "AS-IS" */
36 /*     TO THE RECIPIENT WITHOUT WARRANTY OF ANY KIND, INCLUDING ANY */
37 /*     WARRANTIES OF PERFORMANCE OR MERCHANTABILITY OR FITNESS FOR A */
38 /*     PARTICULAR USE OR PURPOSE (AS SET FORTH IN UNITED STATES UCC */
39 /*     SECTIONS 2312-2313) OR FOR ANY PURPOSE WHATSOEVER, FOR THE */
40 /*     SOFTWARE AND RELATED MATERIALS, HOWEVER USED. */
41 
42 /*     IN NO EVENT SHALL CALTECH, ITS JET PROPULSION LABORATORY, OR NASA */
43 /*     BE LIABLE FOR ANY DAMAGES AND/OR COSTS, INCLUDING, BUT NOT */
44 /*     LIMITED TO, INCIDENTAL OR CONSEQUENTIAL DAMAGES OF ANY KIND, */
45 /*     INCLUDING ECONOMIC DAMAGE OR INJURY TO PROPERTY AND LOST PROFITS, */
46 /*     REGARDLESS OF WHETHER CALTECH, JPL, OR NASA BE ADVISED, HAVE */
47 /*     REASON TO KNOW, OR, IN FACT, SHALL KNOW OF THE POSSIBILITY. */
48 
49 /*     RECIPIENT BEARS ALL RISK RELATING TO QUALITY AND PERFORMANCE OF */
50 /*     THE SOFTWARE AND ANY RELATED MATERIALS, AND AGREES TO INDEMNIFY */
51 /*     CALTECH AND NASA FOR ALL THIRD-PARTY CLAIMS RESULTING FROM THE */
52 /*     ACTIONS OF RECIPIENT IN THE USE OF THE SOFTWARE. */
53 
54 /* $ Required_Reading */
55 
56 /*     SPK */
57 
58 /* $ Keywords */
59 
60 /*     EPHEMERIS */
61 
62 /* $ Declarations */
63 /* $ Brief_I/O */
64 
65 /*     Variable  I/O  Description */
66 /*     --------  ---  -------------------------------------------------- */
67 /*     TARG       I   Target body. */
68 /*     ET         I   Target epoch. */
69 /*     REF        I   Target reference frame. */
70 /*     STARG      O   State of target. */
71 
72 /* $ Detailed_Input */
73 
74 /*     TARG        is the standard NAIF ID code for a target body. */
75 
76 /*     ET          is the epoch (ephemeris time) at which the state */
77 /*                 of the target body is to be computed. */
78 
79 /*     REF         is the name of the  reference frame to which the */
80 /*                 vectors returned by the routine should be rotated. */
81 /*                 This may be any frame supported by the SPICELIB frame */
82 /*                 system, including dynamic and other non-inertial */
83 /*                 frames. */
84 
85 /* $ Detailed_Output */
86 
87 /*     STARG       contains the position and velocity of the target */
88 /*                 body, relative to the solar system barycenter, */
89 /*                 at epoch ET. These vectors are rotated into the */
90 /*                 specified  reference frame. Units are always */
91 /*                 km and km/sec. */
92 
93 /* $ Parameters */
94 
95 /*     None. */
96 
97 /* $ Exceptions */
98 
99 /*     1) If insufficient information has not bee "loaded" via the */
100 /*        routine SPKLEF or the PCK kernel loaders, the problem will */
101 /*        be diagnosed by a routine in the call tree of this routine. */
102 
103 /* $ Files */
104 
105 /*     See: $Restrictions. */
106 
107 /* $ Particulars */
108 
109 /*     In order to compute the state of one body relative to another, */
110 /*     the states of the two bodies must be known relative to a third */
111 /*     body. One simple solution is to use the solar system barycenter */
112 /*     as the third body. */
113 
114 /*     Ephemeris data from more than one segment may be required */
115 /*     to determine the state of a body relative to the barycenter. */
116 /*     ZZSPKSB1 reads as many segments as necessary, from as many */
117 /*     files as necessary, using files that have been loaded by */
118 /*     previous calls to SPKLEF (load ephemeris file). */
119 
120 /* $ Examples */
121 
122 /*     In the following code fragment, ZZSPKSB1 is used to display */
123 /*     the distance from Earth (Body 399) to Mars (body 499) at */
124 /*     a series of epochs. */
125 
126 /*        CALL SPKLEF ( 'DE125.SPK', HANDLE ) */
127 /*         . */
128 /*         . */
129 
130 /*        EARTH = 399 */
131 /*        MARS  = 499 */
132 
133 /*        DO WHILE ( EPOCH .LE. END ) */
134 /*           CALL ZZSPKSB1 ( EARTH, EPOCH, 'J2000', SEARTH ) */
135 /*           CALL ZZSPKSB1 ( MARS,  EPOCH, 'J2000', SMARS  ) */
136 
137 /*           CALL VSUB ( SMARS, SEARTH, SMARS ) */
138 /*           WRITE (*,*) EPOCH, VNORM ( SMARS ) */
139 
140 /*           EPOCH = EPOCH + DELTA */
141 /*        END DO */
142 
143 /* $ Restrictions */
144 
145 /*     1) SPICE Private routine. */
146 
147 /*     2) The ephemeris files to be used by ZZSPKSB1 must be loaded */
148 /*        by SPKLEF before ZZSPKSB1 is called. */
149 
150 /* $ Literature_References */
151 
152 /*     NAIF Document 168.0, "S- and P- Kernel (SPK) Specification and */
153 /*     User's Guide" */
154 
155 /* $ Author_and_Institution */
156 
157 /*     W.L. Taber      (JPL) */
158 /*     I.M. Underwood  (JPL) */
159 
160 /* $ Version */
161 
162 /* -    SPICELIB Version 1.0.0, 12-DEC-2004 (NJB) */
163 
164 /*        Based on SPICELIB Version 2.0.2, 20-NOV-2004  (NJB) */
165 
166 /* -& */
167 /* $ Index_Entries */
168 
169 /*     state relative to solar system barycenter */
170 
171 /* -& */
172 /* $ Revisions */
173 
174 /* -    SPICELIB Version 2.0.0, 19-SEP-1995  (WLT) */
175 
176 /*        The routine was simplified by replacing all of the */
177 /*        main body of code with a call to SPKGEO.  By making */
178 /*        this change the routine now supports non-inertial frames. */
179 
180 /* -& */
181 
182 /*     SPICELIB functions */
183 
184 
185 /*     Local variables */
186 
187 
188 /*     Standard SPICE error handling. */
189 
190     if (return_()) {
191 	return 0;
192     } else {
193 	chkin_("ZZSPKSB1", (ftnlen)8);
194     }
195     bary = 0;
196     zzspkgo1_(targ, et, ref, &bary, starg, &lt, ref_len);
197     chkout_("ZZSPKSB1", (ftnlen)8);
198     return 0;
199 } /* zzspksb1_ */
200 
201