/* $Procedure ET2LST ( ET to Local Solar Time ) */
/* Subroutine */ int et2lst_(doublereal *et, integer *body, doublereal *
long__, char *type__, integer *hr, integer *mn, integer *sc, char *
time, char *ampm, ftnlen type_len, ftnlen time_len, ftnlen ampm_len)
{
/* System generated locals */
address a__1[5], a__2[7];
integer i__1[5], i__2[7];
doublereal d__1;
/* Builtin functions */
integer s_cmp(char *, char *, ftnlen, ftnlen);
/* Subroutine */ int s_copy(char *, char *, ftnlen, ftnlen), s_cat(char *,
char **, integer *, integer *, ftnlen);
/* Local variables */
doublereal rate, slat, mins;
char h__[2], m[2];
integer n;
doublereal q;
char s[2];
doublereal angle;
char frame[32];
doublereal range;
extern /* Subroutine */ int chkin_(char *, ftnlen), ucase_(char *, char *,
ftnlen, ftnlen), errch_(char *, char *, ftnlen, ftnlen), dpfmt_(
doublereal *, char *, char *, ftnlen, ftnlen);
logical found;
extern /* Subroutine */ int repmi_(char *, char *, integer *, char *,
ftnlen, ftnlen, ftnlen);
doublereal state[6], slong;
extern /* Subroutine */ int spkez_(integer *, doublereal *, char *, char *
, integer *, doublereal *, doublereal *, ftnlen, ftnlen);
doublereal hours;
extern /* Subroutine */ int ljust_(char *, char *, ftnlen, ftnlen);
extern doublereal twopi_(void);
extern /* Subroutine */ int bodc2n_(integer *, char *, logical *, ftnlen);
extern doublereal pi_(void);
char bodnam[36];
doublereal lt;
integer frcode;
extern /* Subroutine */ int cidfrm_(integer *, integer *, char *, logical
*, ftnlen);
extern doublereal brcktd_(doublereal *, doublereal *, doublereal *);
extern /* Subroutine */ int reclat_(doublereal *, doublereal *,
doublereal *, doublereal *), rmaind_(doublereal *, doublereal *,
doublereal *, doublereal *);
doublereal secnds;
extern /* Subroutine */ int pgrrec_(char *, doublereal *, doublereal *,
doublereal *, doublereal *, doublereal *, doublereal *, ftnlen);
char bpmkwd[32];
integer hrampm;
doublereal tmpang;
extern /* Subroutine */ int gdpool_(char *, integer *, integer *, integer
*, doublereal *, logical *, ftnlen);
char amorpm[4];
doublereal tmpsec;
extern /* Subroutine */ int sigerr_(char *, ftnlen), chkout_(char *,
ftnlen), dtpool_(char *, logical *, integer *, char *, ftnlen,
ftnlen), setmsg_(char *, ftnlen), errint_(char *, integer *,
ftnlen);
doublereal mylong, spoint[3];
extern logical return_(void);
char kwtype[1];
extern /* Subroutine */ int intstr_(integer *, char *, ftnlen);
char mytype[32];
doublereal lat;
/* $ Abstract */
/* Given an ephemeris epoch ET, compute the local solar time for */
/* an object on the surface of a body at a specified longitude. */
/* $ Disclaimer */
/* THIS SOFTWARE AND ANY RELATED MATERIALS WERE CREATED BY THE */
/* CALIFORNIA INSTITUTE OF TECHNOLOGY (CALTECH) UNDER A U.S. */
/* GOVERNMENT CONTRACT WITH THE NATIONAL AERONAUTICS AND SPACE */
/* ADMINISTRATION (NASA). THE SOFTWARE IS TECHNOLOGY AND SOFTWARE */
/* PUBLICLY AVAILABLE UNDER U.S. EXPORT LAWS AND IS PROVIDED "AS-IS" */
/* TO THE RECIPIENT WITHOUT WARRANTY OF ANY KIND, INCLUDING ANY */
/* WARRANTIES OF PERFORMANCE OR MERCHANTABILITY OR FITNESS FOR A */
/* PARTICULAR USE OR PURPOSE (AS SET FORTH IN UNITED STATES UCC */
/* SECTIONS 2312-2313) OR FOR ANY PURPOSE WHATSOEVER, FOR THE */
/* SOFTWARE AND RELATED MATERIALS, HOWEVER USED. */
/* IN NO EVENT SHALL CALTECH, ITS JET PROPULSION LABORATORY, OR NASA */
/* BE LIABLE FOR ANY DAMAGES AND/OR COSTS, INCLUDING, BUT NOT */
/* LIMITED TO, INCIDENTAL OR CONSEQUENTIAL DAMAGES OF ANY KIND, */
/* INCLUDING ECONOMIC DAMAGE OR INJURY TO PROPERTY AND LOST PROFITS, */
/* REGARDLESS OF WHETHER CALTECH, JPL, OR NASA BE ADVISED, HAVE */
/* REASON TO KNOW, OR, IN FACT, SHALL KNOW OF THE POSSIBILITY. */
/* RECIPIENT BEARS ALL RISK RELATING TO QUALITY AND PERFORMANCE OF */
/* THE SOFTWARE AND ANY RELATED MATERIALS, AND AGREES TO INDEMNIFY */
/* CALTECH AND NASA FOR ALL THIRD-PARTY CLAIMS RESULTING FROM THE */
/* ACTIONS OF RECIPIENT IN THE USE OF THE SOFTWARE. */
/* $ Required_Reading */
/* TIME */
/* $ Keywords */
/* TIME */
/* $ Declarations */
/* $ Brief_I/O */
/* VARIABLE I/O DESCRIPTION */
/* -------- --- -------------------------------------------------- */
/* ET I Epoch in seconds past J2000 epoch */
/* BODY I ID-code of the body of interest */
/* LONG I Longitude of surface point (RADIANS) */
/* TYPE I Type of longitude 'PLANETOCENTRIC', etc. */
/* HR O Local hour on a "24 hour" clock */
/* MN O Minutes past the hour */
/* SC O Seconds past the minute */
/* TIME O String giving local time on 24 hour clock */
/* AMPM O String giving time on A.M./ P.M. scale */
/* $ Detailed_Input */
/* ET is the epoch expressed in TDB seconds past */
/* the J2000 epoch at which a local time is desired. */
/* BODY is the NAIF ID-code of a body on which local */
/* time is to be measured. */
/* LONG is the longitude (either planetocentric or */
/* planetographic) in radians of the site on the */
/* surface of body for which local time should be */
/* computed. */
/* TYPE is the form of longitude supplied by the variable */
/* LONG. Allowed values are 'PLANETOCENTRIC' and */
/* 'PLANETOGRAPHIC'. Note the case of the letters */
/* in TYPE is insignificant. Both 'PLANETOCENTRIC' */
/* and 'planetocentric' are recognized. */
/* $ Detailed_Output */
/* HR is the local "hour" of the site specified at the */
/* epoch ET. Note that an "hour" of local time does not */
/* have the same duration as an hour measured by */
/* conventional clocks. It is simply a representation */
/* of an angle. See the "Particulars" section for a more */
/* complete discussion of the meaning of local time. */
/* MN is the number of "minutes" past the hour of the */
/* local time of the site at the epoch ET. Again note */
/* that a "local minute" is not the same as a minute */
/* you would measure with conventional clocks. */
/* SC is the number of "seconds" past the minute of the */
/* local time of the site at the epoch ET. Again note */
/* that a "local second" is not the same as a second */
/* you would measure with conventional clocks. */
/* TIME is a string expressing the local time */
/* on a "24 hour" local clock. */
/* AMPM is a string expressing the local time on a "12 hour" */
/* local clock together with the traditional AM/PM */
/* label to indicate whether the sun has crossed */
/* the local zenith meridian. */
/* $ Parameters */
/* None. */
/* $ Exceptions */
/* 1) This routine defines local solar time for any point on the */
/* surface of the Sun to be 12:00:00 noon. */
/* 2) If the TYPE of the coordinates is not recognized, the */
/* error 'SPICE(UNKNOWNSYSTEM)' will be signaled. */
/* 3) If the body-fixed frame to associate with BODY cannot be */
/* determined, the error 'SPICE(CANTFINDFRAME)' is signaled. */
/* 4) If insufficient data is available to compute the */
/* location of the sun in body-fixed coordinates, the */
/* error will be diagnosed by a routine called by this one. */
/* 5) If the BODY#_PM keyword required to determine the body */
/* rotation sense is not found in the POOL or if it is found but */
/* is not a numeric keyword with at least two elements, the error */
/* 'SPICE(CANTGETROTATIONTYPE)' is signaled. */
/* $ Files */
/* Suitable SPK and PCK files must be loaded prior to calling this */
/* routine so that the body-fixed position of the sun relative to */
/* BODY can be computed. The PCK files must contain the standard */
/* BODY#_PM keyword need by this routine to determine the body */
/* rotation sense. */
/* When the input longitude is planetographic, the default */
/* interpretation of this value can be overridden using the optional */
/* kernel variable */
/* BODY<body ID>_PGR_POSITIVE_LON */
/* which is normally defined via loading a text kernel. */
/* $ Particulars */
/* This routine returns the local solar time at a user */
/* specified location on a user specified body. */
/* Let SUNLNG be the planetocentric longitude (in degrees) of */
/* the sun as viewed from the center of the body of interest. */
/* Let SITLNG be the planetocentric longitude (in degrees) of */
/* the site for which local time is desired. */
/* We define local time to be 12 + (SITLNG - SUNLNG)/15 */
/* (where appropriate care is taken to map ( SITLNG - SUNLNG ) */
/* into the range from -180 to 180). */
/* Using this definition, we see that from the point of view */
/* of this routine, local solar time is simply a measure of angles */
/* between meridians on the surface of a body. Consequently, */
/* this routine is not appropriate for computing "local times" */
/* in the sense of Pacific Standard Time. For computing times */
/* relative to standard time zones on earth, see the routines */
/* TIMOUT and STR2ET. */
/* Regarding planetographic longitude */
/* ---------------------------------- */
/* In the planetographic coordinate system, longitude is defined */
/* using the spin sense of the body. Longitude is positive to the */
/* west if the spin is prograde and positive to the east if the spin */
/* is retrograde. The spin sense is given by the sign of the first */
/* degree term of the time-dependent polynomial for the body's prime */
/* meridian Euler angle "W": the spin is retrograde if this term is */
/* negative and prograde otherwise. For the sun, planets, most */
/* natural satellites, and selected asteroids, the polynomial */
/* expression for W may be found in a SPICE PCK kernel. */
/* The earth, moon, and sun are exceptions: planetographic longitude */
/* is measured positive east for these bodies. */
/* If you wish to override the default sense of positive */
/* planetographic longitude for a particular body, you can do so by */
/* defining the kernel variable */
/* BODY<body ID>_PGR_POSITIVE_LON */
/* where <body ID> represents the NAIF ID code of the body. This */
/* variable may be assigned either of the values */
/* 'WEST' */
/* 'EAST' */
/* For example, you can have this routine treat the longitude */
/* of the earth as increasing to the west using the kernel */
/* variable assignment */
/* BODY399_PGR_POSITIVE_LON = 'WEST' */
/* Normally such assignments are made by placing them in a text */
/* kernel and loading that kernel via FURNSH. */
/* $ Examples */
/* The following code fragment illustrates how you */
/* could print the local time at a site on Mars with */
/* planetographic longitude 326.17 deg E at epoch ET. */
/* (This example assumes all required SPK and PCK files have */
/* been loaded). */
/* Convert the longitude to radians, set the type of the longitude */
/* and make up a mnemonic for Mars' ID-code. */
/* LONG = 326.17 * RPD() */
/* TYPE = 'PLANETOGRAPHIC' */
/* MARS = 499 */
/* CALL ET2LST ( ET, MARS, LONG, TYPE, HR, MN, SC, TIME, AMPM ) */
/* WRITE (*,*) 'The local time at Mars 326.17 degrees E ' */
/* WRITE (*,*) 'planetographic longitude is: ', AMPM */
/* $ Restrictions */
/* This routine relies on being able to determine the name */
/* of the body-fixed frame associated with BODY through the */
/* frames subsystem. If the BODY specified is NOT one of the */
/* nine planets or their satellites, you will need to load */
/* an appropriate frame definition kernel that contains */
/* the relationship between the body id and the body-fixed frame */
/* name. See the FRAMES required reading for more details */
/* on specifying this relationship. */
/* The routine determines the body rotation sense using the PCK */
/* keyword BODY#_PM. Therefore, you will need to a text PCK file */
/* defining the complete set of the standard PCK body rotation */
/* keywords for the body of interest. The text PCK file must be */
/* loaded independently of whether a binary PCK file providing */
/* rotation data for the same body is loaded or not. */
/* Although it is not currently the case for any of the Solar System */
/* bodies, it is possible that the retrograde rotation rate of a */
/* body would be slower than the orbital rate of the body rotation */
/* around the Sun. The routine does not account for such cases; for */
/* them it will compute incorrect the local time progressing */
/* backwards. */
/* $ Literature_References */
/* None. */
/* $ Author_and_Institution */
/* W.L. Taber (JPL) */
/* $ Version */
/* - SPICELIB Version 3.0.2, 18-APR-2014 (BVS) */
/* Minor edits to long error messages. */
/* - SPICELIB Version 3.0.1, 09-SEP-2009 (EDW) */
/* Header edits: deleted a spurious C$ marker from the */
/* "Detailed_Output" section. The existence of the marker */
/* caused a failure in the HTML documentation creation script. */
/* Deleted the "Revisions" section as it contained several */
/* identical entries from the "Version" section. */
/* Corrected order of header sections. */
/* - SPICELIB Version 3.0.0, 28-OCT-2006 (BVS) */
/* Bug fix: incorrect computation of the local time for the */
/* bodies with the retrograde rotation causing the local time to */
/* flow backwards has been fixed. The local time for all types of */
/* bodies now progresses as expected -- midnight, increasing AM */
/* hours, noon, increasing PM hours, next midnight, and so on. */
/* - SPICELIB Version 2.0.0, 03-NOV-2005 (NJB) */
/* Bug fix: treatment of planetographic longitude has been */
/* updated to be consistent with the SPICE planetographic/ */
/* rectangular coordinate conversion routines. The effect of */
/* this change is that the default sense of positive longitude */
/* for the moon is now east; also, the default sense of positive */
/* planetographic longitude now may be overridden for any body */
/* (see Particulars above). */
/* Updated to remove non-standard use of duplicate arguments */
/* in RMAIND calls. */
/* - SPICELIB Version 1.1.0, 24-MAR-1998 (WLT) */
/* The integer variable SUN was never initialized in the */
/* previous version of the routine. Now it is set to */
/* the proper value of 10. */
/* - SPICELIB Version 1.0.0, 9-JUL-1997 (WLT) */
/* -& */
/* $ Index_Entries */
/* Compute the local time for a point on a body. */
/* -& */
/* SPICELIB Functions */
/* Local parameters */
/* Local Variables */
/* Standard SPICE error handling. */
if (return_()) {
return 0;
}
chkin_("ET2LST", (ftnlen)6);
ljust_(type__, mytype, type_len, (ftnlen)32);
ucase_(mytype, mytype, (ftnlen)32, (ftnlen)32);
if (s_cmp(mytype, "PLANETOGRAPHIC", (ftnlen)32, (ftnlen)14) == 0) {
/* Find planetocentric longitude corresponding to the input */
/* longitude. We first represent in rectangular coordinates */
/* a surface point having zero latitude, zero altitude, and */
/* the input planetographic longitude. We then find the */
/* planetocentric longitude of this point. */
/* Since PGRREC accepts a body name, map the input code to */
/* a name, if possible. Otherwise, just convert the input code */
/* to a string. */
bodc2n_(body, bodnam, &found, (ftnlen)36);
if (! found) {
intstr_(body, bodnam, (ftnlen)36);
}
/* Convert planetographic coordinates to rectangular coordinates. */
/* All we care about here is longitude. Set the other inputs */
/* as follows: */
/* Latitude = 0 */
/* Altitude = 0 */
/* Equatorial radius = 1 */
/* Flattening factor = 0 */
pgrrec_(bodnam, long__, &c_b4, &c_b4, &c_b6, &c_b4, spoint, (ftnlen)
36);
/* The output MYLONG is planetocentric longitude. The other */
/* outputs are not used. Note that the variable RANGE appears */
/* later in another RECLAT call; it's not used after that. */
reclat_(spoint, &range, &mylong, &lat);
} else if (s_cmp(mytype, "PLANETOCENTRIC", (ftnlen)32, (ftnlen)14) == 0) {
mylong = *long__;
} else {
setmsg_("The coordinate system '#' is not a recognized system of lon"
"gitude. The recognized systems are 'PLANETOCENTRIC' and 'PL"
"ANETOGRAPHIC'. ", (ftnlen)134);
errch_("#", type__, (ftnlen)1, type_len);
sigerr_("SPICE(UNKNOWNSYSTEM)", (ftnlen)20);
chkout_("ET2LST", (ftnlen)6);
return 0;
}
/* It's always noon on the surface of the sun. */
if (*body == 10) {
*hr = 12;
*mn = 0;
*sc = 0;
s_copy(time, "12:00:00", time_len, (ftnlen)8);
s_copy(ampm, "12:00:00 P.M.", ampm_len, (ftnlen)13);
chkout_("ET2LST", (ftnlen)6);
return 0;
}
/* Get the body-fixed position of the sun. */
cidfrm_(body, &frcode, frame, &found, (ftnlen)32);
if (! found) {
setmsg_("The body-fixed frame associated with body # could not be de"
"termined. This information needs to be \"loaded\" via a fra"
"mes definition kernel. See frames.req for more details. ", (
ftnlen)174);
errint_("#", body, (ftnlen)1);
sigerr_("SPICE(CANTFINDFRAME)", (ftnlen)20);
chkout_("ET2LST", (ftnlen)6);
return 0;
}
spkez_(&c__10, et, frame, "LT+S", body, state, <, (ftnlen)32, (ftnlen)4)
;
reclat_(state, &range, &slong, &slat);
angle = mylong - slong;
/* Force the angle into the region from -PI to PI */
d__1 = twopi_();
rmaind_(&angle, &d__1, &q, &tmpang);
angle = tmpang;
if (angle > pi_()) {
angle -= twopi_();
}
/* Get the rotation sense of the body and invert the angle if the */
/* rotation sense is retrograde. Use the BODY#_PM PCK keyword to */
/* determine the sense of the body rotation. */
s_copy(bpmkwd, "BODY#_PM", (ftnlen)32, (ftnlen)8);
repmi_(bpmkwd, "#", body, bpmkwd, (ftnlen)32, (ftnlen)1, (ftnlen)32);
dtpool_(bpmkwd, &found, &n, kwtype, (ftnlen)32, (ftnlen)1);
if (! found || *(unsigned char *)kwtype != 'N' || n < 2) {
setmsg_("The rotation type for the body # could not be determined be"
"cause the # keyword was either not found in the POOL or or i"
"t was not of the expected type and/or dimension. This keywor"
"d is usually provided via a planetary constants kernel. See "
"pck.req for more details. ", (ftnlen)265);
errint_("#", body, (ftnlen)1);
errch_("#", bpmkwd, (ftnlen)1, (ftnlen)32);
sigerr_("SPICE(CANTGETROTATIONTYPE)", (ftnlen)26);
chkout_("ET2LST", (ftnlen)6);
return 0;
} else {
/* If the rotation rate is negative, invert the angle. */
gdpool_(bpmkwd, &c__2, &c__1, &n, &rate, &found, (ftnlen)32);
if (rate < 0.) {
angle = -angle;
}
}
/* Convert the angle to "angle seconds" before or after local noon. */
secnds = angle * 86400. / twopi_();
secnds = brcktd_(&secnds, &c_b32, &c_b33);
/* Get the hour, and minutes components of the local time. */
rmaind_(&secnds, &c_b34, &hours, &tmpsec);
rmaind_(&tmpsec, &c_b35, &mins, &secnds);
/* Construct the integer components of the local time. */
*hr = (integer) hours + 12;
*mn = (integer) mins;
*sc = (integer) secnds;
/* Set the A.M./P.M. components of local time. */
if (*hr == 24) {
*hr = 0;
hrampm = 12;
s_copy(amorpm, "A.M.", (ftnlen)4, (ftnlen)4);
} else if (*hr > 12) {
hrampm = *hr - 12;
s_copy(amorpm, "P.M.", (ftnlen)4, (ftnlen)4);
} else if (*hr == 12) {
hrampm = 12;
s_copy(amorpm, "P.M.", (ftnlen)4, (ftnlen)4);
} else if (*hr == 0) {
hrampm = 12;
s_copy(amorpm, "A.M.", (ftnlen)4, (ftnlen)4);
} else {
hrampm = *hr;
s_copy(amorpm, "A.M.", (ftnlen)4, (ftnlen)4);
}
/* Now construct the two strings we need. */
hours = (doublereal) (*hr);
mins = (doublereal) (*mn);
secnds = (doublereal) (*sc);
dpfmt_(&hours, "0x", h__, (ftnlen)2, (ftnlen)2);
dpfmt_(&mins, "0x", m, (ftnlen)2, (ftnlen)2);
dpfmt_(&secnds, "0x", s, (ftnlen)2, (ftnlen)2);
/* Writing concatenation */
i__1[0] = 2, a__1[0] = h__;
i__1[1] = 1, a__1[1] = ":";
i__1[2] = 2, a__1[2] = m;
i__1[3] = 1, a__1[3] = ":";
i__1[4] = 2, a__1[4] = s;
s_cat(time, a__1, i__1, &c__5, time_len);
hours = (doublereal) hrampm;
dpfmt_(&hours, "0x", h__, (ftnlen)2, (ftnlen)2);
/* Writing concatenation */
i__2[0] = 2, a__2[0] = h__;
i__2[1] = 1, a__2[1] = ":";
i__2[2] = 2, a__2[2] = m;
i__2[3] = 1, a__2[3] = ":";
i__2[4] = 2, a__2[4] = s;
i__2[5] = 1, a__2[5] = " ";
i__2[6] = 4, a__2[6] = amorpm;
s_cat(ampm, a__2, i__2, &c__7, ampm_len);
chkout_("ET2LST", (ftnlen)6);
return 0;
} /* et2lst_ */
/* $Procedure XFMSTA ( Transform state between coordinate systems) */
/* Subroutine */ int xfmsta_(doublereal *istate, char *icosys, char *ocosys,
char *body, doublereal *ostate, ftnlen icosys_len, ftnlen ocosys_len,
ftnlen body_len)
{
/* Initialized data */
static char cosys[40*6] = "RECTANGULAR "
"CYLINDRICAL " "LATITUDINAL "
" " "SPHERICAL "
"GEODETIC " "PLANETOGRAPHIC "
" ";
static logical first = TRUE_;
/* System generated locals */
integer i__1, i__2;
doublereal d__1, d__2;
/* Builtin functions */
double sqrt(doublereal);
integer s_rnge(char *, integer, char *, integer);
/* Local variables */
extern /* Subroutine */ int zzbods2c_(integer *, char *, integer *,
logical *, char *, integer *, logical *, ftnlen, ftnlen);
doublereal ivel[3], ipos[3];
extern /* Subroutine */ int vequ_(doublereal *, doublereal *);
integer isys, osys;
doublereal f;
extern /* Subroutine */ int zzctruin_(integer *);
integer i__, j;
doublereal radii[3];
extern /* Subroutine */ int chkin_(char *, ftnlen), errch_(char *, char *,
ftnlen, ftnlen), vpack_(doublereal *, doublereal *, doublereal *,
doublereal *);
extern doublereal dpmax_(void);
logical found;
extern /* Subroutine */ int errdp_(char *, doublereal *, ftnlen), vequg_(
doublereal *, integer *, doublereal *);
doublereal sqtmp;
char isysu[40], osysu[40];
static logical svfnd1;
static integer svctr1[2];
extern logical failed_(void);
doublereal jacobi[9] /* was [3][3] */;
extern /* Subroutine */ int bodvcd_(integer *, char *, integer *, integer
*, doublereal *, ftnlen), georec_(doublereal *, doublereal *,
doublereal *, doublereal *, doublereal *, doublereal *), drdgeo_(
doublereal *, doublereal *, doublereal *, doublereal *,
doublereal *, doublereal *), recgeo_(doublereal *, doublereal *,
doublereal *, doublereal *, doublereal *, doublereal *), dgeodr_(
doublereal *, doublereal *, doublereal *, doublereal *,
doublereal *, doublereal *);
integer bodyid;
extern integer isrchc_(char *, integer *, char *, ftnlen, ftnlen);
static integer svbdid;
extern /* Subroutine */ int latrec_(doublereal *, doublereal *,
doublereal *, doublereal *), drdlat_(doublereal *, doublereal *,
doublereal *, doublereal *), cylrec_(doublereal *, doublereal *,
doublereal *, doublereal *), drdcyl_(doublereal *, doublereal *,
doublereal *, doublereal *);
doublereal toobig;
extern /* Subroutine */ int sphrec_(doublereal *, doublereal *,
doublereal *, doublereal *), drdsph_(doublereal *, doublereal *,
doublereal *, doublereal *), pgrrec_(char *, doublereal *,
doublereal *, doublereal *, doublereal *, doublereal *,
doublereal *, ftnlen), drdpgr_(char *, doublereal *, doublereal *,
doublereal *, doublereal *, doublereal *, doublereal *, ftnlen),
reccyl_(doublereal *, doublereal *, doublereal *, doublereal *),
reclat_(doublereal *, doublereal *, doublereal *, doublereal *),
sigerr_(char *, ftnlen), recsph_(doublereal *, doublereal *,
doublereal *, doublereal *), chkout_(char *, ftnlen), recpgr_(
char *, doublereal *, doublereal *, doublereal *, doublereal *,
doublereal *, doublereal *, ftnlen), dcyldr_(doublereal *,
doublereal *, doublereal *, doublereal *), dlatdr_(doublereal *,
doublereal *, doublereal *, doublereal *), ljucrs_(integer *,
char *, char *, ftnlen, ftnlen), setmsg_(char *, ftnlen), dsphdr_(
doublereal *, doublereal *, doublereal *, doublereal *);
static char svbody[36];
extern /* Subroutine */ int dpgrdr_(char *, doublereal *, doublereal *,
doublereal *, doublereal *, doublereal *, doublereal *, ftnlen);
extern logical return_(void);
integer dim;
extern /* Subroutine */ int mxv_(doublereal *, doublereal *, doublereal *)
;
/* $ Abstract */
/* Transform a state between coordinate systems. */
/* $ Disclaimer */
/* THIS SOFTWARE AND ANY RELATED MATERIALS WERE CREATED BY THE */
/* CALIFORNIA INSTITUTE OF TECHNOLOGY (CALTECH) UNDER A U.S. */
/* GOVERNMENT CONTRACT WITH THE NATIONAL AERONAUTICS AND SPACE */
/* ADMINISTRATION (NASA). THE SOFTWARE IS TECHNOLOGY AND SOFTWARE */
/* PUBLICLY AVAILABLE UNDER U.S. EXPORT LAWS AND IS PROVIDED "AS-IS" */
/* TO THE RECIPIENT WITHOUT WARRANTY OF ANY KIND, INCLUDING ANY */
/* WARRANTIES OF PERFORMANCE OR MERCHANTABILITY OR FITNESS FOR A */
/* PARTICULAR USE OR PURPOSE (AS SET FORTH IN UNITED STATES UCC */
/* SECTIONS 2312-2313) OR FOR ANY PURPOSE WHATSOEVER, FOR THE */
/* SOFTWARE AND RELATED MATERIALS, HOWEVER USED. */
/* IN NO EVENT SHALL CALTECH, ITS JET PROPULSION LABORATORY, OR NASA */
/* BE LIABLE FOR ANY DAMAGES AND/OR COSTS, INCLUDING, BUT NOT */
/* LIMITED TO, INCIDENTAL OR CONSEQUENTIAL DAMAGES OF ANY KIND, */
/* INCLUDING ECONOMIC DAMAGE OR INJURY TO PROPERTY AND LOST PROFITS, */
/* REGARDLESS OF WHETHER CALTECH, JPL, OR NASA BE ADVISED, HAVE */
/* REASON TO KNOW, OR, IN FACT, SHALL KNOW OF THE POSSIBILITY. */
/* RECIPIENT BEARS ALL RISK RELATING TO QUALITY AND PERFORMANCE OF */
/* THE SOFTWARE AND ANY RELATED MATERIALS, AND AGREES TO INDEMNIFY */
/* CALTECH AND NASA FOR ALL THIRD-PARTY CLAIMS RESULTING FROM THE */
/* ACTIONS OF RECIPIENT IN THE USE OF THE SOFTWARE. */
/* $ Required_Reading */
/* None. */
/* $ Keywords */
/* CONVERSION */
/* COORDINATE */
/* EPHEMERIS */
/* STATE */
/* $ Declarations */
/* $ Abstract */
/* This include file defines the dimension of the counter */
/* array used by various SPICE subsystems to uniquely identify */
/* changes in their states. */
/* $ Disclaimer */
/* THIS SOFTWARE AND ANY RELATED MATERIALS WERE CREATED BY THE */
/* CALIFORNIA INSTITUTE OF TECHNOLOGY (CALTECH) UNDER A U.S. */
/* GOVERNMENT CONTRACT WITH THE NATIONAL AERONAUTICS AND SPACE */
/* ADMINISTRATION (NASA). THE SOFTWARE IS TECHNOLOGY AND SOFTWARE */
/* PUBLICLY AVAILABLE UNDER U.S. EXPORT LAWS AND IS PROVIDED "AS-IS" */
/* TO THE RECIPIENT WITHOUT WARRANTY OF ANY KIND, INCLUDING ANY */
/* WARRANTIES OF PERFORMANCE OR MERCHANTABILITY OR FITNESS FOR A */
/* PARTICULAR USE OR PURPOSE (AS SET FORTH IN UNITED STATES UCC */
/* SECTIONS 2312-2313) OR FOR ANY PURPOSE WHATSOEVER, FOR THE */
/* SOFTWARE AND RELATED MATERIALS, HOWEVER USED. */
/* IN NO EVENT SHALL CALTECH, ITS JET PROPULSION LABORATORY, OR NASA */
/* BE LIABLE FOR ANY DAMAGES AND/OR COSTS, INCLUDING, BUT NOT */
/* LIMITED TO, INCIDENTAL OR CONSEQUENTIAL DAMAGES OF ANY KIND, */
/* INCLUDING ECONOMIC DAMAGE OR INJURY TO PROPERTY AND LOST PROFITS, */
/* REGARDLESS OF WHETHER CALTECH, JPL, OR NASA BE ADVISED, HAVE */
/* REASON TO KNOW, OR, IN FACT, SHALL KNOW OF THE POSSIBILITY. */
/* RECIPIENT BEARS ALL RISK RELATING TO QUALITY AND PERFORMANCE OF */
/* THE SOFTWARE AND ANY RELATED MATERIALS, AND AGREES TO INDEMNIFY */
/* CALTECH AND NASA FOR ALL THIRD-PARTY CLAIMS RESULTING FROM THE */
/* ACTIONS OF RECIPIENT IN THE USE OF THE SOFTWARE. */
/* $ Parameters */
/* CTRSIZ is the dimension of the counter array used by */
/* various SPICE subsystems to uniquely identify */
/* changes in their states. */
/* $ Author_and_Institution */
/* B.V. Semenov (JPL) */
/* $ Literature_References */
/* None. */
/* $ Version */
/* - SPICELIB Version 1.0.0, 29-JUL-2013 (BVS) */
/* -& */
/* End of include file. */
/* $ Brief_I/O */
/* VARIABLE I/O DESCRIPTION */
/* -------- --- ------------------------------------------------- */
/* ISTATE I Input state. */
/* ICOSYS I Current (input) coordinate system. */
/* OCOSYS I Desired (output) coordinate system. */
/* BODY I Name or NAIF ID of body with which */
/* coordinates are associated (if applicable). */
/* OSTATE O Converted output state. */
/* $ Detailed_Input */
/* ISTATE is a state vector in the input (ICOSYS) coordinate */
/* system representing position and velocity. */
/* All angular measurements must be in radians. */
/* Note: body radii values taken from the kernel */
/* pool are used when converting to or from geodetic or */
/* planetographic coordinates. It is the user's */
/* responsibility to verify the distance inputs are in */
/* the same units as the radii in the kernel pool, */
/* typically kilometers. */
/* ICOSYS is the name of the coordinate system that the input */
/* state vector (ISTATE) is currently in. */
/* ICOSYS may be any of the following: */
/* 'RECTANGULAR' */
/* 'CYLINDRICAL' */
/* 'LATITUDINAL' */
/* 'SPHERICAL' */
/* 'GEODETIC' */
/* 'PLANETOGRAPHIC' */
/* Leading spaces, trailing spaces, and letter case */
/* are ignored. For example, ' cyLindRical ' would be */
/* accepted. */
/* OCOSYS is the name of the coordinate system that the state */
/* should be converted to. */
/* Please see the description of ICOSYS for details. */
/* BODY is the name or NAIF ID of the body associated with the */
/* planetographic or geodetic coordinate system. */
/* If neither of the coordinate system choices are */
/* geodetic or planetographic, BODY may be an empty */
/* string (' '). */
/* Examples of accepted body names or IDs are: */
/* 'Earth' */
/* '399' */
/* Leading spaces, trailing spaces, and letter case are */
/* ignored. */
/* $ Detailed_Output */
/* OSTATE is the state vector that has been converted to the */
/* output coordinate system (OCOSYS). */
/* $ Parameters */
/* None. */
/* $ Exceptions */
/* 1) If either the input or output coordinate system is not */
/* recognized, the error SPICE(COORDSYSNOTREC) is signaled. */
/* 2) If the input body name cannot be converted to a NAIF ID */
/* (applies to geodetic and planetographic coordinate */
/* systems), the error 'SPICE(IDCODENOTFOUND)' is signaled. */
/* 3) If the input state ISTATE is not valid, meaning the position */
/* but not the velocity is along the z-axis, the error */
/* 'SPICE(INVALIDSTATE)' is signaled. */
/* Note: If both the input position and velocity are along */
/* the z-axis and the output coordinate system is not */
/* rectangular, the velocity can still be calculated even */
/* though the Jacobian is undefined. This case will not */
/* signal an error. An example of the input position and */
/* velocity along the z-axis is below. */
/* Term Value */
/* ----- ------ */
/* x 0 */
/* y 0 */
/* z z */
/* dx/dt 0 */
/* dy/dt 0 */
/* dz/dt dz_dt */
/* 4) If either the input or output coordinate system is */
/* geodetic or planetographic and at least one of the body's */
/* radii is less than or equal to zero, the error */
/* SPICE(INVALIDRADIUS) will be signaled. */
/* 5) If either the input or output coordinate system is */
/* geodetic or planetographic and the difference of the */
/* equatorial and polar radii divided by the equatorial radius */
/* would produce numeric overflow, the error */
/* 'SPICE(INVALIDRADIUS)' will be signaled. */
/* 6) If the product of the Jacobian and velocity components */
/* may lead to numeric overflow, the error */
/* 'SPICE(NUMERICOVERFLOW)' is signaled. */
/* $ Files */
/* SPK, PCK, CK, and FK kernels may be required. */
/* If the input or output coordinate systems are either geodetic or */
/* planetographic, a PCK providing the radii of the body */
/* name BODY must be loaded via FURNSH. */
/* Kernel data are normally loaded once per program run, NOT every */
/* time this routine is called. */
/* $ Particulars */
/* Input Order */
/* ------------------------------------------- */
/* The input and output states will be structured by the */
/* following descriptions. */
/* For rectangular coordinates, the state vector is the following */
/* in which X, Y, and Z are the rectangular position components and */
/* DX, DY, and DZ are the time derivatives of each position */
/* component. */
/* ISTATE = ( X, Y, Z, DX, DY, DZ ) */
/* For cylindrical coordinates, the state vector is the following */
/* in which R is the radius, LONG is the longitudes, Z is the */
/* height, and DR, DLONG, and DZ are the time derivatives of each */
/* position component. */
/* ISTATE = ( R, LONG, Z, DR, DLONG, DZ ) */
/* For latitudinal coordinates, the state vector is the following */
/* in which R is the radius, LONG is the longitude, LAT is the */
/* latitude, and DR, DLONG, and DLAT are the time derivatives of */
/* each position component. */
/* ISTATE = ( R, LONG, LAT, DR, DLONG, DLAT ) */
/* For spherical coordinates, the state vector is the following in */
/* which R is the radius, COLAT is the colatitude, LONG is the */
/* longitude, and DR, DCOLAT, and DLONG are the time derivatives of */
/* each position component. */
/* ISTATE = ( R, COLAT, LONG, DR, DCOLAT, DLONG ) */
/* For geodetic coordinates, the state vector is the following in */
/* which LONG is the longitude, LAT is the latitude, ALT is the */
/* altitude, and DLONG, DLAT, and DALT are the time derivatives of */
/* each position component. */
/* ISTATE = ( LONG, LAT, ALT, DLONG, DLAT, DALT ) */
/* For planetographic coordinates, the state vector is the */
/* following in which LONG is the longitude, LAT is the latitude, */
/* ALT is the altitude, and DLONG, DLAT, and DALT are the time */
/* derivatives of each position component. */
/* ISTATE = ( LONG, LAT, ALT, DLONG, DLAT, DALT ) */
/* Input Boundaries */
/* ------------------------------------------- */
/* There are intervals the input angles must fall within if */
/* the input coordinate system is not rectangular. These */
/* intervals are provided below. */
/* Input variable Input meaning Input interval [rad] */
/* -------------- ------------- ------------------------ */
/* LONG Longitude 0 <= LONG < 2*pi */
/* LAT Latitude -pi/2 <= LAT <= pi/2 */
/* COLAT Colatitude 0 <= COLAT <= pi */
/* $ Examples */
/* The numerical results shown for these examples may differ across */
/* platforms. The results depend on the SPICE kernels used as */
/* input, the compiler and supporting libraries, and the machine */
/* specific arithmetic implementation. */
/* 1) Find the apparent state of Phoebe as seen by CASSINI in the */
/* J2000 frame at 2004 Jun 11 19:32:00. Transform the state */
/* from rectangular to latitudinal coordinates. For verification, */
/* transform the state back from latitudinal to rectangular */
/* coordinates. */
/* Use the meta-kernel shown below to load the required SPICE */
/* kernels. */
/* KPL/MK */
/* File name: xfmsta_ex1.tm */
/* This meta-kernel is intended to support operation of SPICE */
/* example programs. The kernels shown here should not be */
/* assumed to contain adequate or correct versions of data */
/* required by SPICE-based user applications. */
/* In order for an application to use this meta-kernel, the */
/* kernels referenced here must be present in the user's */
/* current working directory. */
/* The names and contents of the kernels referenced */
/* by this meta-kernel are as follows: */
/* File name Contents */
/* --------- -------- */
/* cpck05Mar2004.tpc Planet orientation and */
/* radii */
/* naif0009.tls Leapseconds */
/* 020514_SE_SAT105.bsp Satellite ephemeris for */
/* Saturn */
/* 030201AP_SK_SM546_T45.bsp CASSINI ephemeris */
/* 981005_PLTEPH-DE405S.bsp Planetary ephemeris */
/* \begindata */
/* KERNELS_TO_LOAD = ( 'naif0009.tls' , */
/* '020514_SE_SAT105.bsp' , */
/* '030201AP_SK_SM546_T45.bsp' , */
/* '981005_PLTEPH-DE405S.bsp', */
/* 'cpck05Mar2004.tpc' ) */
/* End of meta-kernel */
/* Example code begins here. */
/* PROGRAM EX1_XFMSTA */
/* IMPLICIT NONE */
/* C */
/* C Local parameters */
/* C */
/* C METAKR is the meta-kernel's filename. */
/* C */
/* CHARACTER*(*) METAKR */
/* PARAMETER ( METAKR = 'xfmsta_ex1.tm' ) */
/* CHARACTER*(*) FORM */
/* PARAMETER ( FORM = '(F16.6, F16.6, F16.6)' ) */
/* C */
/* C Local variables */
/* C */
/* C STAREC is the state of Phoebe with respect to CASSINI in */
/* C rectangular coordinates. STALAT is the state rotated into */
/* C latitudinal coordinates. STREC2 is the state transformed */
/* C back into rectangular coordinates from latitudinal. */
/* C */
/* DOUBLE PRECISION STAREC (6) */
/* DOUBLE PRECISION STALAT (6) */
/* DOUBLE PRECISION STREC2 (6) */
/* C */
/* C ET is the ephemeris time (TDB) corresponding to the */
/* C observation. */
/* C */
/* DOUBLE PRECISION ET */
/* DOUBLE PRECISION LT */
/* INTEGER I */
/* C */
/* C The required kernels must be loaded. */
/* C */
/* CALL FURNSH ( METAKR ) */
/* C */
/* C Calculate the state at 2004 Jun 11 19:32:00 UTC. */
/* C */
/* CALL STR2ET ( '2004-JUN-11-19:32:00', ET ) */
/* C */
/* C Calculate the apparent state of Phoebe as seen by */
/* C CASSINI in the J2000 frame. */
/* C */
/* CALL SPKEZR ( 'PHOEBE', ET, 'IAU_PHOEBE', 'LT+S', */
/* . 'CASSINI', STAREC, LT ) */
/* C */
/* C Transform the state from rectangular to latitudinal. */
/* C Notice that since neither the input nor output */
/* C coordinate frames are 'geodetic' or 'planetographic', */
/* C the input for the body name is a blank string. */
/* C */
/* CALL XFMSTA ( STAREC, 'RECTANGULAR', 'LATITUDINAL', ' ', */
/* . STALAT ) */
/* C */
/* C Transform the state back to rectangular from latitudinal */
/* C for verification. This result should be very similar to */
/* C STAREC. */
/* C */
/* CALL XFMSTA ( STALAT, 'LATITUDINAL', 'RECTANGULAR',' ', */
/* . STREC2 ) */
/* C */
/* C Report the results. */
/* C */
/* WRITE (*,*) ' ' */
/* WRITE (*,*) 'Phoebe as seen by CASSINI - rectangular' */
/* WRITE (*,*) ' Position [km]:' */
/* WRITE (*,FORM) (STAREC(I), I = 1, 3) */
/* WRITE (*,*) ' Velocity [km/s]:' */
/* WRITE (*,FORM) (STAREC(I), I = 4, 6) */
/* WRITE (*,*) ' ' */
/* WRITE (*,*) 'Phoebe as seen by CASSINI - latitudinal' */
/* WRITE (*,*) ' Position [km, rad, rad]:' */
/* WRITE (*,FORM) (STALAT(I), I = 1, 3) */
/* WRITE (*,*) ' Velocity [km/s, rad/s, rad/s]:' */
/* WRITE (*,FORM) (STALAT(I), I = 4, 6) */
/* WRITE (*,*) ' ' */
/* WRITE (*,*) 'Verification: ' */
/* WRITE (*,*) 'Phoebe as seen by CASSINI - rectangular' */
/* WRITE (*,*) ' Position [km]:' */
/* WRITE (*,FORM) (STREC2(I), I = 1, 3) */
/* WRITE (*,*) ' Velocity [km/s]:' */
/* WRITE (*,FORM) (STREC2(I), I = 4, 6) */
/* END */
/* When this program was executed using gfortran on a PC Linux */
/* 64 bit environment, the output was: */
/* Phoebe as seen by CASSINI - rectangular */
/* Position [km]: */
/* -1982.639762 -934.530471 -166.562595 */
/* Velocity [km/s]: */
/* 3.970832 -3.812496 -2.371663 */
/* Phoebe as seen by CASSINI - latitudinal */
/* Position [km, rad, rad]: */
/* 2198.169858 -2.701121 -0.075846 */
/* Velocity [km/s, rad/s, rad/s]: */
/* -1.780939 0.002346 -0.001144 */
/* Verification: */
/* Phoebe as seen by CASSINI - rectangular */
/* Position [km]: */
/* -1982.639762 -934.530471 -166.562595 */
/* Velocity [km/s]: */
/* 3.970832 -3.812496 -2.371663 */
/* 2) Transform a given state from cylindrical to planetographic */
/* coordinates with respect to Earth. */
/* Use the meta-kernel shown below to load the required SPICE */
/* kernels. */
/* KPL/MK */
/* File name: xfmsta_ex2.tm */
/* This meta-kernel is intended to support operation of SPICE */
/* example programs. The kernels shown here should not be */
/* assumed to contain adequate or correct versions of data */
/* required by SPICE-based user applications. */
/* In order for an application to use this meta-kernel, the */
/* kernels referenced here must be present in the user's */
/* current working directory. */
/* The names and contents of the kernels referenced */
/* by this meta-kernel are as follows: */
/* File name Contents */
/* --------- -------- */
/* cpck05Mar2004.tpc Planet orientation and */
/* radii */
/* \begindata */
/* KERNELS_TO_LOAD = ( 'cpck05Mar2004.tpc' ) */
/* \begintext */
/* End of meta-kernel */
/* Example code begins here. */
/* PROGRAM EX2_XFMSTA */
/* IMPLICIT NONE */
/* C */
/* C Local parameters */
/* C */
/* C METAKR is the meta-kernel's filename. */
/* C */
/* CHARACTER*(*) METAKR */
/* PARAMETER ( METAKR = 'xfmsta_ex2.tm' ) */
/* CHARACTER*(*) FORM */
/* PARAMETER ( FORM = '(F16.6, F16.6, F16.6)' ) */
/* C */
/* C Local variables */
/* C */
/* C STACYL is the state in cylindrical coordinates. */
/* C */
/* DOUBLE PRECISION STACYL (6) */
/* C */
/* C STAPLN is the state transformed into planetographic */
/* C coordinates. */
/* C */
/* DOUBLE PRECISION STAPLN (6) */
/* C */
/* C STCYL2 is the state transformed back into */
/* C cylindrical coordinates from planetographic. */
/* C */
/* DOUBLE PRECISION STCYL2 (6) */
/* INTEGER I */
/* DATA STACYL / 1.0D0, 0.5D0, 0.5D0, 0.2D0, 0.1D0, -0.2D0 / */
/* C */
/* C The required kernels must be loaded. */
/* C */
/* CALL FURNSH ( METAKR ) */
/* C */
/* C Transform the state from cylindrical to planetographic. */
/* C Note that since one of the coordinate systems is */
/* C planetographic, the body name must be input. */
/* C */
/* CALL XFMSTA ( STACYL, 'CYLINDRICAL', 'PLANETOGRAPHIC', */
/* . 'EARTH', STAPLN ) */
/* C */
/* C Transform the state back to cylindrical from */
/* C planetographic for verification. The result should be very */
/* C close to STACYL. */
/* C */
/* CALL XFMSTA ( STAPLN, 'PLANETOGRAPHIC', 'CYLINDRICAL', */
/* . 'EARTH', STCYL2 ) */
/* C */
/* C Report the results. */
/* C */
/* WRITE (*,*) 'Cylindrical state' */
/* WRITE (*,*) ' Position [km, rad, km]:' */
/* WRITE (*,FORM) (STACYL(I), I = 1, 3) */
/* WRITE (*,*) ' Velocity [km/s, rad/s, km/s]:' */
/* WRITE (*,FORM) (STACYL(I), I = 4, 6) */
/* WRITE (*,*) ' ' */
/* WRITE (*,*) 'Planetographic state' */
/* WRITE (*,*) ' Position [rad, rad, km]:' */
/* WRITE (*,FORM) (STAPLN(I), I = 1, 3) */
/* WRITE (*,*) ' Velocity [rad/s, rad/s, km/s]:' */
/* WRITE (*,FORM) (STAPLN(I), I = 4, 6) */
/* WRITE (*,*) ' ' */
/* WRITE (*,*) 'Verification: Cylindrical state' */
/* WRITE (*,*) ' Position [km, rad, km]:' */
/* WRITE (*,FORM) (STCYL2(I), I = 1, 3) */
/* WRITE (*,*) ' Velocity [km/s, rad/s, km/s]:' */
/* WRITE (*,FORM) (STCYL2(I), I = 4, 6) */
/* END */
/* When this program was executed using gfortran on a PC Linux */
/* 64 bit environment, the output was: */
/* Cylindrical state */
/* Position [km, rad, km]: */
/* 1.000000 0.500000 0.500000 */
/* Velocity [km/s, rad/s, km/s]: */
/* 0.200000 0.100000 -0.200000 */
/* Planetographic state */
/* Position [rad, rad, km]: */
/* 0.500000 1.547727 -6356.238467 */
/* Velocity [rad/s, rad/s, km/s]: */
/* 0.100000 -0.004721 -0.195333 */
/* Verification: Cylindrical state */
/* Position [km, rad, km]: */
/* 1.000000 0.500000 0.500000 */
/* Velocity [km/s, rad/s, km/s]: */
/* 0.200000 0.100000 -0.200000 */
/* $ Restrictions */
/* None. */
/* $ Literature_References */
/* None. */
/* $ Author_and_Institution */
/* S.C. Krening (JPL) */
/* B.V. Semenov (JPL) */
/* $ Version */
/* - SPICELIB Version 1.0.0 22-APR-2014 (SCK)(BVS) */
/* -& */
/* $ Index_Entries */
/* state transformation between coordinate systems */
/* convert state */
/* -& */
/* SPICELIB functions */
/* Local parameters */
/* Potentially large numbers produced by transforming the */
/* velocity using the Jacobian must not exceed DPMAX()/MARGIN: */
/* The size of each coordinate system name must not exceed */
/* CHSIZ characters. */
/* NCOSYS is the number of coordinate systems supported by */
/* this routine. */
/* The following integer parameters represent the coordinate */
/* systems supported by this routine. */
/* Saved body name length. */
/* Local variables */
/* COSYS is the array of supported coordinate system names. */
/* ISYSU and OSYSU are the input and output coordinate systems */
/* from the user that are made insensitive to case or leading and */
/* trailing spaces. */
/* IPOS and IVEL are the input position and velocity translated */
/* into rectangular. */
/* For transformations including either geodetic or planetographic */
/* coordinate systems, RADII is an array of the radii values */
/* associated with the input body. These values will be loaded */
/* from the kernel pool. */
/* JACOBI is the Jacobian matrix that converts the velocity */
/* coordinates between systems. */
/* The flattening coefficient, F, is calculated when either */
/* geodetic or planetographic coordinate systems are included */
/* in the transformation. */
/* SQTMP and TOOBIG are used to check for possible numeric */
/* overflow situations. */
/* BODYID and DIM are only used when the input or output coordinate */
/* systems are geodetic or planetographic. The BODYID is the NAID ID */
/* associated with the input body name. DIM is used while retrieving */
/* the radii from the kernel pool. */
/* ISYS and OSYS are the integer codes corresponding to the */
/* input and output coordinate systems. I and J are iterators. */
/* Saved name/ID item declarations. */
/* Saved variables */
/* Saved name/ID items. */
/* Assign the names of the coordinate systems to a character */
/* array in which each coordinate system name is located at */
/* the index of the integer ID of the coordinate system. */
/* Initial values. */
/* There are three main sections of this routine: */
/* 1) Error handling and initialization. */
/* 2) Conversion of the input to rectangular coordinates. */
/* 3) Conversion from rectangular to the output coordinates. */
/* Error handling and initialization */
/* ---------------------------------------------------------------- */
/* Standard SPICE error handling. */
if (return_()) {
return 0;
}
chkin_("XFMSTA", (ftnlen)6);
/* Initialization. */
if (first) {
/* Initialize counter. */
zzctruin_(svctr1);
first = FALSE_;
}
/* Remove initial and trailing spaces. */
/* Convert the input coordinate systems to upper case. */
ljucrs_(&c__0, icosys, isysu, icosys_len, (ftnlen)40);
ljucrs_(&c__0, ocosys, osysu, ocosys_len, (ftnlen)40);
/* Check to see if the input and output coordinate systems */
/* provided by the user are acceptable. Store the integer */
/* code of the input and output coordinate systems into */
/* ISYS and OSYS. */
isys = isrchc_(isysu, &c__6, cosys, (ftnlen)40, (ftnlen)40);
osys = isrchc_(osysu, &c__6, cosys, (ftnlen)40, (ftnlen)40);
/* If the coordinate systems are not acceptable, an error is */
/* signaled. */
if (isys == 0 || osys == 0) {
if (isys == 0 && osys == 0) {
/* Both the input and the output coordinate systems were not */
/* recognized. */
setmsg_("Input coordinate system # and output coordinate system "
"# are not recognized.", (ftnlen)76);
errch_("#", icosys, (ftnlen)1, icosys_len);
errch_("#", ocosys, (ftnlen)1, ocosys_len);
sigerr_("SPICE(COORDSYSNOTREC)", (ftnlen)21);
chkout_("XFMSTA", (ftnlen)6);
return 0;
} else if (isys == 0) {
/* The input coordinate system was not recognized. */
setmsg_("Input coordinate system # was not recognized", (ftnlen)
44);
errch_("#", icosys, (ftnlen)1, icosys_len);
sigerr_("SPICE(COORDSYSNOTREC)", (ftnlen)21);
chkout_("XFMSTA", (ftnlen)6);
return 0;
} else {
/* The output coordinate system was not recognized. */
setmsg_("Output coordinate system # was not recognized", (ftnlen)
45);
errch_("#", ocosys, (ftnlen)1, ocosys_len);
sigerr_("SPICE(COORDSYSNOTREC)", (ftnlen)21);
chkout_("XFMSTA", (ftnlen)6);
return 0;
}
}
/* If the input and output coordinate systems are equal, set the */
/* output equal to the input since no conversion needs to take */
/* place. */
if (isys == osys) {
vequg_(istate, &c__6, ostate);
chkout_("XFMSTA", (ftnlen)6);
return 0;
}
/* If converting to or from either geodetic or planetographic, the */
/* NAIF ID must be found from the input body name BODY. If the */
/* body name does not have a valid NAIF ID code, an error is */
/* signaled. If the NAIF ID is valid, the radii of the body are */
/* located and the flattening coefficient is calculated. */
if (osys == 5 || osys == 6 || isys == 5 || isys == 6) {
/* Find the NAIF ID code */
zzbods2c_(svctr1, svbody, &svbdid, &svfnd1, body, &bodyid, &found, (
ftnlen)36, body_len);
/* If the body's name was found, find the body's radii and */
/* compute flattening coefficient. Otherwise, signal an error. */
if (found) {
bodvcd_(&bodyid, "RADII", &c__3, &dim, radii, (ftnlen)5);
if (failed_()) {
chkout_("XFMSTA", (ftnlen)6);
return 0;
}
/* If either radius is less than or equal to zero, an error is */
/* signaled. */
if (radii[2] <= 0. || radii[0] <= 0.) {
setmsg_("At least one radii is less than or equal to zero. T"
"he equatorial radius has a value of # and the polar "
"radius has has a value of #.", (ftnlen)131);
errdp_("#", radii, (ftnlen)1);
errdp_("#", &radii[2], (ftnlen)1);
sigerr_("SPICE(INVALIDRADIUS)", (ftnlen)20);
chkout_("XFMSTA", (ftnlen)6);
return 0;
}
/* If the difference of the equatorial and polar radii */
/* divided by the equatorial radius is greater than DPMAX, */
/* a numeric overflow may occur, so an error is signaled. */
if (sqrt((d__1 = radii[0] - radii[2], abs(d__1))) / sqrt((abs(
radii[0]))) >= sqrt(dpmax_())) {
setmsg_("The equatorial radius for # has a value of # and a "
"polar radius of #. The flattening coefficient cannot"
" be calculated due to numeric overflow.", (ftnlen)142)
;
errch_("#", body, (ftnlen)1, body_len);
errdp_("#", radii, (ftnlen)1);
errdp_("#", &radii[2], (ftnlen)1);
sigerr_("SPICE(INVALIDRADIUS)", (ftnlen)20);
chkout_("XFMSTA", (ftnlen)6);
return 0;
}
f = (radii[0] - radii[2]) / radii[0];
} else {
setmsg_("The input body name # does not have a valid NAIF ID cod"
"e.", (ftnlen)57);
errch_("#", body, (ftnlen)1, body_len);
sigerr_("SPICE(IDCODENOTFOUND)", (ftnlen)21);
chkout_("XFMSTA", (ftnlen)6);
return 0;
}
}
/* Conversion of the input to rectangular coordinates */
/* ---------------------------------------------------------------- */
/* First, the position and velocity coordinates will be converted */
/* into rectangular coordinates. If the input system is not */
/* rectangular, then the velocity coordinates must be translated */
/* into rectangular using the Jacobian. If the input system is */
/* rectangular, then the input state must simply be saved into IPOS */
/* and IVEL. */
/* TOOBIG is used for preventing numerical overflow. The square */
/* roots of values are used to safely check if overflow will occur. */
toobig = sqrt(dpmax_() / 100.);
if (isys != 1) {
/* To rectangular... */
if (isys == 2) {
/* ... from cylindrical */
cylrec_(istate, &istate[1], &istate[2], ipos);
drdcyl_(istate, &istate[1], &istate[2], jacobi);
} else if (isys == 3) {
/* ... from latitudinal */
latrec_(istate, &istate[1], &istate[2], ipos);
drdlat_(istate, &istate[1], &istate[2], jacobi);
} else if (isys == 4) {
/* ... from spherical */
sphrec_(istate, &istate[1], &istate[2], ipos);
drdsph_(istate, &istate[1], &istate[2], jacobi);
} else if (isys == 5) {
/* ... from geodetic */
georec_(istate, &istate[1], &istate[2], radii, &f, ipos);
if (failed_()) {
chkout_("XFMSTA", (ftnlen)6);
return 0;
}
drdgeo_(istate, &istate[1], &istate[2], radii, &f, jacobi);
} else if (isys == 6) {
/* ... from planetographic */
pgrrec_(body, istate, &istate[1], &istate[2], radii, &f, ipos,
body_len);
if (failed_()) {
chkout_("XFMSTA", (ftnlen)6);
return 0;
}
drdpgr_(body, istate, &istate[1], &istate[2], radii, &f, jacobi,
body_len);
} else {
setmsg_("This error should never occur. This is an intermediate "
"step in which a non-rectangular input state should be tr"
"ansferred to rectangular. The input coordinate system i"
"s not recognized, yet was not caught by an earlier check."
, (ftnlen)224);
sigerr_("SPICE(BUG1)", (ftnlen)11);
chkout_("XFMSTA", (ftnlen)6);
return 0;
}
/* Some DRD* routines are not error free. Be safe and check */
/* FAILED to not use un-initialized JACOBI. */
if (failed_()) {
chkout_("XFMSTA", (ftnlen)6);
return 0;
}
/* If the multiplication of the Jacobian and velocity can cause */
/* overflow, signal an error. */
for (i__ = 1; i__ <= 3; ++i__) {
for (j = 1; j <= 3; ++j) {
sqtmp = sqrt((d__1 = jacobi[(i__1 = i__ + j * 3 - 4) < 9 && 0
<= i__1 ? i__1 : s_rnge("jacobi", i__1, "xfmsta_", (
ftnlen)1054)], abs(d__1))) * sqrt((d__2 = istate[(
i__2 = j + 2) < 6 && 0 <= i__2 ? i__2 : s_rnge("ista"
"te", i__2, "xfmsta_", (ftnlen)1054)], abs(d__2)));
if (sqtmp > toobig) {
setmsg_("The product of the Jacobian and velocity may ca"
"use numeric overflow.", (ftnlen)68);
sigerr_("SPICE(NUMERICOVERFLOW)", (ftnlen)22);
chkout_("XFMSTA", (ftnlen)6);
return 0;
}
}
}
/* Transform the velocity into rectangular coordinates. */
mxv_(jacobi, &istate[3], ivel);
} else if (isys == 1) {
/* If the input coordinate system is rectangular, the input */
/* position does not need to be translated into rectangular. */
vequ_(istate, ipos);
vequ_(&istate[3], ivel);
} else {
setmsg_("This error should never occur. This is an ELSE statement. I"
"f the input coordinate system is not rectangular, the IF sho"
"uld be executed. If the input coordinate system is rectangul"
"ar, the ELSE IF should be executed.", (ftnlen)214);
sigerr_("SPICE(BUG2)", (ftnlen)11);
chkout_("XFMSTA", (ftnlen)6);
return 0;
}
/* Conversion from rectangular into the output coordinates */
/* ---------------------------------------------------------------- */
/* Convert to the output coordinate system. If the output */
/* coordinate system is not rectangular, four calculations must */
/* be made: */
/* 1) Verify the position and velocity are not along the z-axis. */
/* If the position and velocity are along the z-axis, the */
/* velocity can still be converted even though the */
/* Jacobian is not defined. If the position is along the */
/* z-axis but the velocity is not, the velocity cannot be */
/* converted to the output coordinate system. */
/* 2) Calculate the Jacobian from rectangular to the output */
/* coordinate system and verify the product of the Jacobian */
/* and velocity will not cause numeric overflow. */
/* 3) Transform the position to the output coordinate system. */
/* 4) Transform the velocity to the output coordinates using */
/* the Jacobian and the rectangular velocity IVEL. */
if (osys != 1) {
/* From rectangular for the case when the input position is along */
/* the z-axis ... */
if (abs(ipos[0]) + abs(ipos[1]) == 0.) {
if (abs(ivel[0]) + abs(ivel[1]) == 0.) {
/* If the velocity is along the z-axis, then the velocity */
/* can be computed in the output coordinate frame even */
/* though the Jacobian is not defined. */
if (osys == 2) {
/* ... to cylindrical */
vpack_(&c_b56, &c_b56, &ivel[2], &ostate[3]);
reccyl_(ipos, ostate, &ostate[1], &ostate[2]);
} else if (osys == 3) {
/* ... to latitudinal */
vpack_(&ivel[2], &c_b56, &c_b56, &ostate[3]);
reclat_(ipos, ostate, &ostate[1], &ostate[2]);
} else if (osys == 4) {
/* ... to spherical */
vpack_(&ivel[2], &c_b56, &c_b56, &ostate[3]);
recsph_(ipos, ostate, &ostate[1], &ostate[2]);
} else if (osys == 5) {
/* ... to geodetic */
vpack_(&c_b56, &c_b56, &ivel[2], &ostate[3]);
recgeo_(ipos, radii, &f, ostate, &ostate[1], &ostate[2]);
} else if (osys == 6) {
/* ... to planetographic */
vpack_(&c_b56, &c_b56, &ivel[2], &ostate[3]);
recpgr_(body, ipos, radii, &f, ostate, &ostate[1], &
ostate[2], body_len);
} else {
setmsg_("This error should never occur. This is an inter"
"mediate step in which a position and velocity al"
"ong the z-axis are converted to a non-rectangula"
"r coordinate system from rectangular. The output"
" coordinate system is not recognized, yet was no"
"t caught by an earlier check.", (ftnlen)268);
sigerr_("SPICE(BUG3)", (ftnlen)11);
chkout_("XFMSTA", (ftnlen)6);
return 0;
}
/* The output state has been calculated for the special */
/* case of the position and velocity existing along the */
/* z-axis. */
chkout_("XFMSTA", (ftnlen)6);
return 0;
} else {
/* The Jacobian is undefined and the velocity cannot be */
/* converted since it is not along the z-axis. */
/* Signal an error. */
setmsg_("Invalid input state: z axis.", (ftnlen)28);
sigerr_("SPICE(INVALIDSTATE)", (ftnlen)19);
chkout_("XFMSTA", (ftnlen)6);
return 0;
}
}
/* From rectangular for cases when the input position is not along */
/* the z-axis ... */
if (osys == 2) {
/* ... to cylindrical */
dcyldr_(ipos, &ipos[1], &ipos[2], jacobi);
reccyl_(ipos, ostate, &ostate[1], &ostate[2]);
} else if (osys == 3) {
/* ... to latitudinal */
dlatdr_(ipos, &ipos[1], &ipos[2], jacobi);
reclat_(ipos, ostate, &ostate[1], &ostate[2]);
} else if (osys == 4) {
/* ... to spherical */
dsphdr_(ipos, &ipos[1], &ipos[2], jacobi);
recsph_(ipos, ostate, &ostate[1], &ostate[2]);
} else if (osys == 5) {
/* ... to geodetic */
dgeodr_(ipos, &ipos[1], &ipos[2], radii, &f, jacobi);
recgeo_(ipos, radii, &f, ostate, &ostate[1], &ostate[2]);
} else if (osys == 6) {
/* ... to planetographic */
dpgrdr_(body, ipos, &ipos[1], &ipos[2], radii, &f, jacobi,
body_len);
recpgr_(body, ipos, radii, &f, ostate, &ostate[1], &ostate[2],
body_len);
} else {
setmsg_("This error should never occur. This is an intermediate "
"step in which a state is converted to a non-rectangular "
"coordinate system from rectangular. The output coordinat"
"e system is not recognized, yet was not caught by an ear"
"lier check.", (ftnlen)234);
sigerr_("SPICE(BUG4)", (ftnlen)11);
chkout_("XFMSTA", (ftnlen)6);
return 0;
}
/* Many D*DR and REC* routines are not error free. Be safe and */
/* check FAILED to not use un-initialized JACOBI. */
if (failed_()) {
chkout_("XFMSTA", (ftnlen)6);
return 0;
}
/* If the multiplication of the Jacobian and velocity can cause */
/* overflow, signal an error. */
for (i__ = 1; i__ <= 3; ++i__) {
for (j = 1; j <= 3; ++j) {
sqtmp = sqrt((d__1 = jacobi[(i__1 = i__ + j * 3 - 4) < 9 && 0
<= i__1 ? i__1 : s_rnge("jacobi", i__1, "xfmsta_", (
ftnlen)1314)], abs(d__1))) * sqrt((d__2 = ivel[(i__2 =
j - 1) < 3 && 0 <= i__2 ? i__2 : s_rnge("ivel", i__2,
"xfmsta_", (ftnlen)1314)], abs(d__2)));
if (sqtmp > toobig) {
setmsg_("The product of the Jacobian and velocity may ca"
"use numeric overflow.", (ftnlen)68);
sigerr_("SPICE(NUMERICOVERFLOW)", (ftnlen)22);
chkout_("XFMSTA", (ftnlen)6);
return 0;
}
}
}
/* Calculate the velocity in the output coordinate system. */
mxv_(jacobi, ivel, &ostate[3]);
} else if (osys == 1) {
/* If the output coordinate system is rectangular, the position */
/* and velocity components of the output state are set equal to */
/* the rectangular IPOS and IVEL, respectively, because the */
/* components have already been converted to rectangular. */
vequ_(ipos, ostate);
vequ_(ivel, &ostate[3]);
} else {
setmsg_("This error should never occur. This is an ELSE statement. I"
"f the output coordinate system is not rectangular, the IF sh"
"ould be executed. If the output coordinate system is rectang"
"ular, the ELSE IF should be executed.", (ftnlen)216);
sigerr_("SPICE(BUG5)", (ftnlen)11);
chkout_("XFMSTA", (ftnlen)6);
return 0;
}
chkout_("XFMSTA", (ftnlen)6);
return 0;
} /* xfmsta_ */
void pgrrec_c ( ConstSpiceChar * body,
SpiceDouble lon,
SpiceDouble lat,
SpiceDouble alt,
SpiceDouble re,
SpiceDouble f,
SpiceDouble rectan[3] )
/*
-Brief_I/O
VARIABLE I/O DESCRIPTION
-------- --- --------------------------------------------------
body I Body with which coordinate system is associated.
lon I Planetographic longitude of a point (radians).
lat I Planetographic latitude of a point (radians).
alt I Altitude of a point above reference spheroid.
re I Equatorial radius of the reference spheroid.
f I Flattening coefficient.
rectan O Rectangular coordinates of the point.
-Detailed_Input
body Name of the body with which the planetographic
coordinate system is associated.
`body' is used by this routine to look up from the
kernel pool the prime meridian rate coefficient giving
the body's spin sense. See the Files and Particulars
header sections below for details.
lon Planetographic longitude of the input point. This is
the angle between the prime meridian and the meridian
containing the input point. For bodies having
prograde (aka direct) rotation, the direction of
increasing longitude is positive west: from the +X
axis of the rectangular coordinate system toward the
-Y axis. For bodies having retrograde rotation, the
direction of increasing longitude is positive east:
from the +X axis toward the +Y axis.
The earth, moon, and sun are exceptions:
planetographic longitude is measured positive east for
these bodies.
The default interpretation of longitude by this
and the other planetographic coordinate conversion
routines can be overridden; see the discussion in
Particulars below for details.
Longitude is measured in radians. On input, the range
of longitude is unrestricted.
lat Planetographic latitude of the input point. For a
point P on the reference spheroid, this is the angle
between the XY plane and the outward normal vector at
P. For a point P not on the reference spheroid, the
planetographic latitude is that of the closest point
to P on the spheroid.
Latitude is measured in radians. On input, the
range of latitude is unrestricted.
alt Altitude of point above the reference spheroid.
Units of `alt' must match those of `re'.
re Equatorial radius of a reference spheroid. This
spheroid is a volume of revolution: its horizontal
cross sections are circular. The shape of the
spheroid is defined by an equatorial radius `re' and
a polar radius `rp'. Units of `re' must match those of
`alt'.
f Flattening coefficient =
(re-rp) / re
where `rp' is the polar radius of the spheroid, and the
units of `rp' match those of `re'.
-Detailed_Output
rectan The rectangular coordinates of the input point. See
the discussion below in the Particulars header section
for details.
The units associated with `rectan' are those associated
with the inputs `alt' and `re'.
-Parameters
None.
-Exceptions
1) If the body name `body' cannot be mapped to a NAIF ID code,
and if `body' is not a string representation of an integer,
the error SPICE(IDCODENOTFOUND) will be signaled.
2) If the kernel variable
BODY<ID code>_PGR_POSITIVE_LON
is present in the kernel pool but has a value other
than one of
'EAST'
'WEST'
the error SPICE(INVALIDOPTION) will be signaled. Case
and blanks are ignored when these values are interpreted.
3) If polynomial coefficients for the prime meridian of `body'
are not available in the kernel pool, and if the kernel
variable BODY<ID code>_PGR_POSITIVE_LON is not present in
the kernel pool, the error SPICE(MISSINGDATA) will be signaled.
4) If the equatorial radius is non-positive, the error
SPICE(VALUEOUTOFRANGE) is signaled.
5) If the flattening coefficient is greater than or equal to one,
the error SPICE(VALUEOUTOFRANGE) is signaled.
6) The error SPICE(EMPTYSTRING) is signaled if the input
string `body' does not contain at least one character, since the
input string cannot be converted to a Fortran-style string in
this case.
7) The error SPICE(NULLPOINTER) is signaled if the input string
pointer `body' is null.
-Files
This routine expects a kernel variable giving body's prime
meridian angle as a function of time to be available in the
kernel pool. Normally this item is provided by loading a PCK
file. The required kernel variable is named
BODY<body ID>_PM
where <body ID> represents a string containing the NAIF integer
ID code for `body'. For example, if `body' is "JUPITER", then
the name of the kernel variable containing the prime meridian
angle coefficients is
BODY599_PM
See the PCK Required Reading for details concerning the prime
meridian kernel variable.
The optional kernel variable
BODY<body ID>_PGR_POSITIVE_LON
also is normally defined via loading a text kernel. When this
variable is present in the kernel pool, the prime meridian
coefficients for `body' are not required by this routine. See the
Particulars section below for details.
-Particulars
Given the planetographic coordinates of a point, this routine
returns the body-fixed rectangular coordinates of the point. The
body-fixed rectangular frame is that having the X-axis pass
through the 0 degree latitude 0 degree longitude direction, the
Z-axis pass through the 90 degree latitude direction, and the
Y-axis equal to the cross product of the unit Z-axis and X-axis
vectors.
The planetographic definition of latitude is identical to the
planetodetic (also called "geodetic" in SPICE documentation)
definition. In the planetographic coordinate system, latitude is
defined using a reference spheroid. The spheroid is
characterized by an equatorial radius and a polar radius. For a
point P on the spheroid, latitude is defined as the angle between
the X-Y plane and the outward surface normal at P. For a point P
off the spheroid, latitude is defined as the latitude of the
nearest point to P on the spheroid. Note if P is an interior
point, for example, if P is at the center of the spheroid, there
may not be a unique nearest point to P.
In the planetographic coordinate system, longitude is defined
using the spin sense of the body. Longitude is positive to the
west if the spin is prograde and positive to the east if the spin
is retrograde. The spin sense is given by the sign of the first
degree term of the time-dependent polynomial for the body's prime
meridian Euler angle "W": the spin is retrograde if this term is
negative and prograde otherwise. For the sun, planets, most
natural satellites, and selected asteroids, the polynomial
expression for W may be found in a SPICE PCK kernel.
The earth, moon, and sun are exceptions: planetographic longitude
is measured positive east for these bodies.
If you wish to override the default sense of positive longitude
for a particular body, you can do so by defining the kernel
variable
BODY<body ID>_PGR_POSITIVE_LON
where <body ID> represents the NAIF ID code of the body. This
variable may be assigned either of the values
'WEST'
'EAST'
For example, you can have this routine treat the longitude
of the earth as increasing to the west using the kernel
variable assignment
BODY399_PGR_POSITIVE_LON = 'WEST'
Normally such assignments are made by placing them in a text
kernel and loading that kernel via furnsh_c.
The definition of this kernel variable controls the behavior of
the CSPICE planetographic routines
pgrrec_c
recpgr_c
dpgrdr_c
drdpgr_c
It does not affect the other CSPICE coordinate conversion
routines.
-Examples
Numerical results shown for this example may differ between
platforms as the results depend on the SPICE kernels used as
input and the machine specific arithmetic implementation.
1) Find the rectangular coordinates of the point having Mars
planetographic coordinates:
longitude = 90 degrees west
latitude = 45 degrees north
altitude = 300 km
#include <stdio.h>
#include "SpiceUsr.h"
int main()
{
/.
Local variables
./
SpiceDouble alt;
SpiceDouble f;
SpiceDouble lat;
SpiceDouble lon;
SpiceDouble radii [3];
SpiceDouble re;
SpiceDouble rectan [3];
SpiceDouble rp;
SpiceInt n;
/.
Load a PCK file containing a triaxial
ellipsoidal shape model and orientation
data for Mars.
./
furnsh_c ( "pck00008.tpc" );
/.
Look up the radii for Mars. Although we
omit it here, we could first call badkpv_c
to make sure the variable BODY499_RADII
has three elements and numeric data type.
If the variable is not present in the kernel
pool, bodvrd_c will signal an error.
./
bodvrd_c ( "MARS", "RADII", 3, &n, radii );
/.
Compute flattening coefficient.
./
re = radii[0];
rp = radii[2];
f = ( re - rp ) / re;
/.
Do the conversion. Note that we must provide
longitude and latitude in radians.
./
lon = 90.0 * rpd_c();
lat = 45.0 * rpd_c();
alt = 3.e2;
pgrrec_c ( "mars", lon, lat, alt, re, f, rectan );
printf ( "\n"
"Planetographic coordinates:\n"
"\n"
" Longitude (deg) = %18.9e\n"
" Latitude (deg) = %18.9e\n"
" Altitude (km) = %18.9e\n"
"\n"
"Ellipsoid shape parameters:\n"
"\n"
" Equatorial radius (km) = %18.9e\n"
" Polar radius (km) = %18.9e\n"
" Flattening coefficient = %18.9e\n"
"\n"
"Rectangular coordinates:\n"
"\n"
" X (km) = %18.9e\n"
" Y (km) = %18.9e\n"
" Z (km) = %18.9e\n"
"\n",
lon / rpd_c(),
lat / rpd_c(),
alt,
re,
rp,
f,
rectan[0],
rectan[1],
rectan[2] );
return ( 0 );
}
Output from this program should be similar to the following
(rounding and formatting differ across platforms):
Planetographic coordinates:
Longitude (deg) = 9.000000000e+01
Latitude (deg) = 4.500000000e+01
Altitude (km) = 3.000000000e+02
Ellipsoid shape parameters:
Equatorial radius (km) = 3.396190000e+03
Polar radius (km) = 3.376200000e+03
Flattening coefficient = 5.886007556e-03
Rectangular coordinates:
X (km) = 1.604650025e-13
Y (km) = -2.620678915e+03
Z (km) = 2.592408909e+03
2) Below is a table showing a variety of rectangular coordinates
and the corresponding Mars planetographic coordinates. The
values are computed using the reference spheroid having radii
Equatorial radius: 3397
Polar radius: 3375
Note: the values shown above may not be current or suitable
for your application.
Corresponding rectangular and planetographic coordinates are
listed to three decimal places.
rectan[0] rectan[1] rectan[2] lon lat alt
------------------------------------------------------------------
3397.000 0.000 0.000 0.000 0.000 0.000
-3397.000 0.000 0.000 180.000 0.000 0.000
-3407.000 0.000 0.000 180.000 0.000 10.000
-3387.000 0.000 0.000 180.000 0.000 -10.000
0.000 -3397.000 0.000 90.000 0.000 0.000
0.000 3397.000 0.000 270.000 0.000 0.000
0.000 0.000 3375.000 0.000 90.000 0.000
0.000 0.000 -3375.000 0.000 -90.000 0.000
0.000 0.000 0.000 0.000 90.000 -3375.000
3) Below we show the analogous relationships for the earth,
using the reference ellipsoid radii
Equatorial radius: 6378.140
Polar radius: 6356.750
Note the change in longitudes for points on the +/- Y axis
for the earth vs the Mars values.
rectan[0] rectan[1] rectan[2] lon lat alt
------------------------------------------------------------------
6378.140 0.000 0.000 0.000 0.000 0.000
-6378.140 0.000 0.000 180.000 0.000 0.000
-6388.140 0.000 0.000 180.000 0.000 10.000
-6368.140 0.000 0.000 180.000 0.000 -10.000
0.000 -6378.140 0.000 270.000 0.000 0.000
0.000 6378.140 0.000 90.000 0.000 0.000
0.000 0.000 6356.750 0.000 90.000 0.000
0.000 0.000 -6356.750 0.000 -90.000 0.000
0.000 0.000 0.000 0.000 90.000 -6356.750
-Restrictions
None.
-Author_and_Institution
C.H. Acton (JPL)
N.J. Bachman (JPL)
H.A. Neilan (JPL)
B.V. Semenov (JPL)
W.L. Taber (JPL)
-Literature_References
None.
-Version
-CSPICE Version 1.0.0, 26-DEC-2004 (CHA) (NJB) (HAN) (BVS) (WLT)
-Index_Entries
convert planetographic to rectangular coordinates
-&
*/
{ /* Begin pgrrec_c */
/*
Participate in error tracing.
*/
if ( return_c() )
{
return;
}
chkin_c ( "pgrrec_c" );
/*
Check the input string body to make sure the pointer is non-null
and the string length is non-zero.
*/
CHKFSTR ( CHK_STANDARD, "pgrrec_c", body );
/*
Call the f2c'd Fortran routine.
*/
pgrrec_ ( ( char * ) body,
( doublereal * ) &lon,
( doublereal * ) &lat,
( doublereal * ) &alt,
( doublereal * ) &re,
( doublereal * ) &f,
( doublereal * ) rectan,
( ftnlen ) strlen(body) );
chkout_c ( "pgrrec_c" );
} /* End pgrrec_c */