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Index Page gfrr_c
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Procedure Abstract Required_Reading Keywords Brief_I/O Detailed_Input | Detailed_Output Parameters Exceptions Files Particulars Examples | Restrictions Literature_References Author_and_Institution Version Index_Entries
#### Procedure
       gfrr_c (GF, range rate search )

       void gfrr_c ( ConstSpiceChar     * target,
                     ConstSpiceChar     * abcorr,
                     ConstSpiceChar     * obsrvr,
                     ConstSpiceChar     * relate,
                     SpiceDouble          refval,
                     SpiceDouble          adjust,
                     SpiceDouble          step,
                     SpiceInt             nintvls,
                     SpiceCell          * cnfine,
                     SpiceCell          * result  )
#### Abstract
       Determine time intervals for which a specified constraint
       on the observer-target range rate is met.
#### Required_Reading
       GF
       NAIF_IDS
       SPK
       TIME
       WINDOWS
#### Keywords
       EPHEMERIS
       EVENT
       GEOMETRY
       SEARCH
       WINDOW
#### Brief_I/O
       VARIABLE  I/O  DESCRIPTION
       --------  ---  --------------------------------------------------
       SPICE_GF_CNVTOL
                  P   Convergence tolerance.
       target     I   Name of the target body.
       abcorr     I   Aberration correction flag.
       obsrvr     I   Name of the observing body.
       relate     I   Relational operator.
       refval     I   Reference value.
       adjust     I   Adjustment value for absolute extrema searches.
       step       I   Step size used for locating extrema and roots.
       nintvls    I   Workspace window interval count.
       cnfine    I-O  SPICE window to which the search is confined.
       result     O   SPICE window containing results.
#### Detailed_Input
       target      is the name of a target body. Optionally, you may supply
                   the integer ID code for the object as an integer string.
                   For example both "MOON" and "301" are legitimate strings
                   that indicate the moon is the target body.

                   The target and observer define a position vector that
                   points from the observer to the target. The derivative
                   with respect to time of the length of this vector is the
                   "range rate" used by this routine as the geometric
                   quantity of interest.

                   Case and leading or trailing blanks are not significant
                   in the string `target'.

       abcorr      is the description of the aberration corrections to apply
                   to the state evaluations to account for one-way light
                   time and stellar aberration.

                   This routine accepts the same aberration corrections as
                   does the SPICE routine spkezr_c. See the header of spkezr_c
                   for a detailed description of the aberration correction
                   options. For convenience, the options are listed below:

                      "NONE"     Apply no correction. Returns the "true"
                                 geometric state.

                      "LT"       "Reception" case: correct for
                                 one-way light time using a Newtonian
                                 formulation.

                      "LT+S"     "Reception" case: correct for
                                 one-way light time and stellar
                                 aberration using a Newtonian
                                 formulation.

                      "CN"       "Reception" case: converged
                                 Newtonian light time correction.

                      "CN+S"     "Reception" case: converged
                                 Newtonian light time and stellar
                                 aberration corrections.

                      "XLT"      "Transmission" case: correct for
                                 one-way light time using a Newtonian
                                 formulation.

                      "XLT+S"    "Transmission" case: correct for
                                 one-way light time and stellar
                                 aberration using a Newtonian
                                 formulation.

                      "XCN"      "Transmission" case: converged
                                 Newtonian light time correction.

                      "XCN+S"    "Transmission" case: converged
                                 Newtonian light time and stellar
                                 aberration corrections.

                   Case and leading or trailing blanks are not significant
                   in the string `abcorr'.

       obsrvr      is the name of an observing body. Optionally, you may
                   supply the ID code of the object as an integer string.
                   For example, both "EARTH" and "399" are legitimate
                   strings to indicate that the observer is the Earth.

                   Case and leading or trailing blanks are not significant
                   in the string `obsrvr'.

       relate      is the relational operator that defines the constraint on
                   the range rate of the observer-target vector. The result
                   window found by this routine indicates the time intervals
                   where the constraint is satisfied. Supported values of
                   `relate' and corresponding meanings are shown below:

                      ">"        The range rate value is greater than the
                                 reference value `refval'.

                      "="        The range rate value is equal to the
                                 reference value `refval'.

                      "<"        The range rate value is less than the
                                 reference value `refval'.

                      "ABSMAX"   The range rate value is at an absolute
                                 maximum.

                      "ABSMIN"   The range rate value is at an absolute
                                 minimum.

                      "LOCMAX"   The range rate value is at a local
                                 maximum.

                      "LOCMIN"   The range rate value is at a local
                                 minimum.

                   `relate' may be used to specify an "adjusted" absolute
                   extremum constraint: this requires the range rate to be
                   within a specified offset relative to an absolute
                   extremum. The argument `adjust' (described below) is used
                   to specify this offset.

                   Local extrema are considered to exist only in the
                   interiors of the intervals comprising the confinement
                   window:  a local extremum cannot exist at a boundary
                   point of the confinement window.

                   Case and leading or trailing blanks are not
                   significant in the string `relate'.

       refval      is the double precision reference value used together
                   with the argument `relate' to define an equality or
                   inequality to satisfy by the range rate of the
                   observer-target vector. See the discussion of `relate'
                   above for further information.

                   The units of `refval' are km/s.

       adjust      is a double precision value used to modify searches for
                   absolute extrema: when `relate' is set to "ABSMAX" or
                   "ABSMIN" and `adjust' is set to a positive value, gfrr_c
                   finds times when the range rate is within `adjust'
                   kilometers/second of the specified extreme value.

                   For `relate' set to "ABSMAX", the `result' window contains
                   time intervals when the range rate has
                   values between absmax - adjust and `absmax'.

                   For `relate' set to "ABSMIN", the `result' window contains
                   time intervals when the range rate has
                   values between `absmin' and absmin + adjust.

                   `adjust' is not used for searches for local extrema,
                   equality or inequality conditions.

       step        is the double precision time step size to use in the
                   search.

                   `step' must be short enough for a search using this step
                   size to locate the time intervals where the range rate
                   function is monotone increasing or decreasing. However,
                   `step' must not be *too* short, or the search will take an
                   unreasonable amount of time.

                   The choice of `step' affects the completeness but not
                   the precision of solutions found by this routine; the
                   precision is controlled by the convergence tolerance.
                   See the discussion of the parameter SPICE_GF_CNVTOL for
                   details.

                   `step' has units of TDB seconds.

       nintvls     is an integer parameter specifying the number of intervals
                   that can be accommodated by each of the dynamically allocated
                   workspace windows used internally by this routine.

                   In many cases, it's not necessary to compute an accurate
                   estimate of how many intervals are needed; rather, the user
                   can pick a size considerably larger than what's really
                   required.

                   However, since excessively large arrays can prevent
                   applications from compiling, linking, or running properly,
                   sometimes `nintvls' must be set according to the actual
                   workspace requirement. A rule of thumb for the number of
                   intervals needed is

                      nintvls  =  2*n  +  ( m / step )

                   where

                      n      is the number of intervals in the confinement
                             window.

                      m      is the measure of the confinement window, in units
                             of seconds.

                      step   is the search step size in seconds.

       cnfine      is a double precision SPICE window that confines the time
                   period over which the specified search is conducted.
                   `cnfine' may consist of a single interval or a collection
                   of intervals.

                   In some cases the confinement window can be used to
                   greatly reduce the time period that must be searched
                   for the desired solution. See the -Particulars section
                   below for further discussion.

                   See the -Examples section below for a code example
                   that shows how to create a confinement window.

                   In some cases the observer's state may be computed at
                   times outside of `cnfine' by as much as 2 seconds. See
                   -Particulars for details.

                   `cnfine' must be declared as a double precision SpiceCell.

                   CSPICE provides the following macro, which declares and
                   initializes the cell

                      SPICEDOUBLE_CELL        ( cnfine, CNFINESZ );

                   where CNFINESZ is the maximum capacity of `cnfine'.
#### Detailed_Output
       cnfine      is the input confinement window, updated if necessary so the
                   control area of its data array indicates the window's size
                   and cardinality. The window data are unchanged.

       result      is the SPICE window of intervals, contained within the
                   confinement window `cnfine', on which the specified
                   constraint is satisfied.

                   `result' must be declared and initialized with sufficient
                   size to capture the full set of time intervals within the
                   search region on which the specified condition is satisfied.

                   If `result' is non-empty on input, its contents will be
                   discarded before gfrr_c conducts its search.

                   The endpoints of the time intervals comprising `result' are
                   interpreted as seconds past J2000 TDB.

                   If the search is for local extrema, or for absolute
                   extrema with `adjust' set to zero, then normally each
                   interval of `result' will be a singleton: the left and
                   right endpoints of each interval will be identical.

                   If no times within the confinement window satisfy the
                   search criteria, `result' will be returned with a
                   cardinality of zero.

                   `result' must be declared as a double precision SpiceCell.

                   CSPICE provides the following macro, which declares and
                   initializes the cell

                      SPICEDOUBLE_CELL        ( result, RESULTSZ );

                   where RESULTSZ is the maximum capacity of `result'.
#### Parameters
       SPICE_GF_CNVTOL

                  is the convergence tolerance used for finding endpoints
                  of the intervals comprising the result window.
                  SPICE_GF_CNVTOL is used to determine when binary searches
                  for roots should terminate: when a root is bracketed
                  within an interval of length SPICE_GF_CNVTOL, the root is
                  considered to have been found.

                  The accuracy, as opposed to precision, of roots found
                  by this routine depends on the accuracy of the input
                  data. In most cases, the accuracy of solutions will be
                  inferior to their precision.

                  SPICE_GF_CNVTOL is declared in the header file SpiceGF.h.
#### Exceptions
       1)  In order for this routine to produce correct results,
           the step size must be appropriate for the problem at hand.
           Step sizes that are too large may cause this routine to miss
           roots; step sizes that are too small may cause this routine
           to run unacceptably slowly and in some cases, find spurious
           roots.

           This routine does not diagnose invalid step sizes, except that
           if the step size is non-positive, an error is signaled by a
           routine in the call tree of this routine.

       2)  Due to numerical errors, in particular,

              - truncation error in time values
              - finite tolerance value
              - errors in computed geometric quantities

           it is *normal* for the condition of interest to not always be
           satisfied near the endpoints of the intervals comprising the
           `result' window. One technique to handle such a situation,
           slightly contract `result' using the window routine wncond_c.

       3)  If the number of intervals `nintvls' is less than 1, the error
           SPICE(VALUEOUTOFRANGE) is signaled.

       4)  If the size of the SPICE window `result' is less than 2 or not
           an even value, the error SPICE(INVALIDDIMENSION) is signaled
           by a routine in the call tree of this routine.

       5)  If the SPICE window `result' has insufficient capacity to
           contain the number of intervals on which the specified
           distance condition is met, an error is signaled by a routine
           in the call tree of this routine.

       6)  If an error (typically cell overflow) occurs during
           window arithmetic, the error is signaled by a routine
           in the call tree of this routine.

       7)  If the relational operator `relate' is not recognized, an
           error is signaled by a routine in the call tree of this
           routine.

       8)  If the aberration correction specifier contains an
           unrecognized value, an error is signaled by a routine in the
           call tree of this routine.

       9)  If `adjust' is negative, an error is signaled by a routine in
           the call tree of this routine.

       10) If `adjust' has a non-zero value when `relate' has any value other
           than "ABSMIN" or "ABSMAX", an error is signaled by a routine
           in the call tree of this routine.

       11) If either of the input body names do not map to NAIF ID
           codes, an error is signaled by a routine in the call tree of
           this routine.

       12) If required ephemerides or other kernel data are not
           available, an error is signaled by a routine in the call tree
           of this routine.

       13) If any of the `target', `abcorr', `obsrvr' or `relate' input
           string pointers is null, the error SPICE(NULLPOINTER) is
           signaled.

       14) If any of the `target', `abcorr', `obsrvr' or `relate' input
           strings has zero length, the error SPICE(EMPTYSTRING) is
           signaled.

       15) If any the `cnfine' or `result' cell arguments has a type
           other than SpiceDouble, the error SPICE(TYPEMISMATCH) is
           signaled.

       16) If memory cannot be allocated to create the temporary variable
           required for the execution of the underlying Fortran routine,
           the error SPICE(MALLOCFAILED) is signaled.
#### Files
       Appropriate SPK and PCK kernels must be loaded by the calling
       program before this routine is called.

       The following data are required:

       -  SPK data: the calling application must load ephemeris data
          for the targets, observer, and any intermediate objects in
          a chain connecting the targets and observer that cover the
          time period specified by the window `cnfine'. If aberration
          corrections are used, the states of target and observer
          relative to the solar system barycenter must be calculable
          from the available ephemeris data. Typically ephemeris data
          are made available by loading one or more SPK files using
          furnsh_c.

       -  In some cases the observer's state may be computed at times
          outside of `cnfine' by as much as 2 seconds; data required to
          compute this state must be provided by loaded kernels. See
          -Particulars for details.

       Kernel data are normally loaded once per program run, NOT every
       time this routine is called.
#### Particulars
       This routine determines if the caller-specified constraint
       condition on the geometric event (range rate) is satisfied for
       any time intervals within the confinement window `cnfine'. If one
       or more such time intervals exist, those intervals are added
       to the `result' window.

       This routine provides a simpler, but less flexible interface
       than does the routine gfevnt_c for conducting searches for
       observer-target range rate value events. Applications that
       require support for progress reporting, interrupt handling,
       non-default step or refinement functions, or non-default
       convergence tolerance should call gfevnt_c rather than this routine.

       Below we discuss in greater detail aspects of this routine's
       solution process that are relevant to correct and efficient
       use of this routine in user applications.

       The Search Process
       ==================

       Regardless of the type of constraint selected by the caller, this
       routine starts the search for solutions by determining the time
       periods, within the confinement window, over which the
       range rate function is monotone increasing and monotone
       decreasing. Each of these time periods is represented by a SPICE
       window. Having found these windows, all of the range rate
       function's local extrema within the confinement window are known.
       Absolute extrema then can be found very easily.

       Within any interval of these "monotone" windows, there will be at
       most one solution of any equality constraint. Since the boundary
       of the solution set for any inequality constraint is contained in
       the union of

       -  the set of points where an equality constraint is met

       -  the boundary points of the confinement window

       the solutions of both equality and inequality constraints can be
       found easily once the monotone windows have been found.

       Step Size
       =========

       The monotone windows (described above) are found using a two-step
       search process. Each interval of the confinement window is
       searched as follows: first, the input step size is used to
       determine the time separation at which the sign of the rate of
       change of range rate will be sampled. Starting at
       the left endpoint of an interval, samples will be taken at each
       step. If a change of sign is found, a root has been bracketed; at
       that point, the time at which the time derivative of the
       range rate is zero can be found by a refinement process, for
       example, using a binary search.

       Note that the optimal choice of step size depends on the lengths
       of the intervals over which the range rate function is monotone:
       the step size should be shorter than the shortest of these
       intervals (within the confinement window).

       The optimal step size is *not* necessarily related to the lengths
       of the intervals comprising the result window. For example, if
       the shortest monotone interval has length 10 days, and if the
       shortest result window interval has length 5 minutes, a step size
       of 9.9 days is still adequate to find all of the intervals in the
       result window. In situations like this, the technique of using
       monotone windows yields a dramatic efficiency improvement over a
       state-based search that simply tests at each step whether the
       specified constraint is satisfied. The latter type of search can
       miss solution intervals if the step size is longer than the
       shortest solution interval.

       Having some knowledge of the relative geometry of the target and
       observer can be a valuable aid in picking a reasonable step size.
       In general, the user can compensate for lack of such knowledge by
       picking a very short step size; the cost is increased computation
       time.

       Note that the step size is not related to the precision with which
       the endpoints of the intervals of the result window are computed.
       That precision level is controlled by the convergence tolerance.

       Convergence Tolerance
       =====================

       As described above, the root-finding process used by this routine
       involves first bracketing roots and then using a search process
       to locate them. "Roots" are both times when local extrema are
       attained and times when the range rate function is equal to a
       reference value. All endpoints of the intervals comprising the
       result window are either endpoints of intervals of the
       confinement window or roots.

       Once a root has been bracketed, a refinement process is used to
       narrow down the time interval within which the root must lie.
       This refinement process terminates when the location of the root
       has been determined to within an error margin called the
       "convergence tolerance." The default convergence tolerance
       used by this routine is set by the parameter SPICE_GF_CNVTOL (defined
       in SpiceGF.h).

       The value of SPICE_GF_CNVTOL is set to a "tight" value so that the
       tolerance doesn't become the limiting factor in the accuracy of
       solutions found by this routine. In general the accuracy of input
       data will be the limiting factor.

       The user may change the convergence tolerance from the default
       SPICE_GF_CNVTOL value by calling the routine gfstol_c, e.g.

          gfstol_c ( tolerance value );

       Call gfstol_c prior to calling this routine. All subsequent
       searches will use the updated tolerance value.

       Setting the tolerance tighter than SPICE_GF_CNVTOL is unlikely to be
       useful, since the results are unlikely to be more accurate.
       Making the tolerance looser will speed up searches somewhat,
       since a few convergence steps will be omitted. However, in most
       cases, the step size is likely to have a much greater effect
       on processing time than would the convergence tolerance.

       The Confinement Window
       ======================

       The simplest use of the confinement window is to specify a time
       interval within which a solution is sought. However, the
       confinement window can, in some cases, be used to make searches
       more efficient. Sometimes it's possible to do an efficient search
       to reduce the size of the time period over which a relatively
       slow search of interest must be performed.

       Certain types of searches require the state of the observer,
       relative to the solar system barycenter, to be computed at times
       slightly outside the confinement window `cnfine'. The time window
       that is actually used is the result of "expanding" `cnfine' by a
       specified amount "T": each time interval of `cnfine' is expanded by
       shifting the interval's left endpoint to the left and the right
       endpoint to the right by T seconds. Any overlapping intervals are
       merged. (The input argument `cnfine' is not modified.)

       The window expansions listed below are additive: if both
       conditions apply, the window expansion amount is the sum of the
       individual amounts.

       -  If a search uses an equality constraint, the time window
          over which the state of the observer is computed is expanded
          by 1 second at both ends of all of the time intervals
          comprising the window over which the search is conducted.

       -  If a search uses stellar aberration corrections, the time
          window over which the state of the observer is computed is
          expanded as described above.

       When light time corrections are used, expansion of the search
       window also affects the set of times at which the light time-
       corrected state of the target is computed.

       In addition to the possible 2 second expansion of the search
       window that occurs when both an equality constraint and stellar
       aberration corrections are used, round-off error should be taken
       into account when the need for data availability is analyzed.
#### Examples
       The numerical results shown for this example 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) Determine the time windows from January 1, 2007 UTC to
          April 1, 2007 UTC for which the sun-moon range rate satisfies the
          relation conditions with respect to a reference value of
          0.3365 km/s radians (this range rate known to occur within the
          search interval). Also determine the time windows corresponding
          to the local maximum and minimum range rate, and the absolute
          maximum and minimum range rate during the search interval.

          Use the meta-kernel shown below to load the required SPICE
          kernels.

             KPL/MK

             File name: gfrr_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
                ---------                     --------
                de421.bsp                     Planetary ephemeris
                pck00009.tpc                  Planet orientation and
                                              radii
                naif0009.tls                  Leapseconds

             \begindata

                KERNELS_TO_LOAD = ( 'de421.bsp',
                                    'pck00009.tpc',
                                    'naif0009.tls'  )

             \begintext

             End of meta-kernel

          Example code begins here.

          /.
             Program gfrr_ex1
          ./
          #include <stdio.h>
          #include <stdlib.h>
          #include <string.h>
          #include "SpiceUsr.h"

          #define       MAXWIN    20000
          #define       TIMFMT    "YYYY-MON-DD HR:MN:SC.###"
          #define       TIMLEN    41
          #define       NLOOPS    7

          int main( )
             {

             /.
             Create the needed windows. Note, one window
             consists of two values, so the total number
             of cell values to allocate is twice
             the number of intervals.
             ./
             SPICEDOUBLE_CELL ( result, 2*MAXWIN );
             SPICEDOUBLE_CELL ( cnfine, 2        );

             SpiceDouble       begtim;
             SpiceDouble       endtim;
             SpiceDouble       step;
             SpiceDouble       adjust;
             SpiceDouble       refval;
             SpiceDouble       beg;
             SpiceDouble       end;

             SpiceChar         begstr [ TIMLEN ];
             SpiceChar         endstr [ TIMLEN ];

             SpiceChar       * target = "MOON";
             SpiceChar       * abcorr = "NONE";
             SpiceChar       * obsrvr = "SUN";

             SpiceInt          count;
             SpiceInt          i;
             SpiceInt          j;

             ConstSpiceChar * relate [NLOOPS] = { "=",
                                                  "<",
                                                  ">",
                                                  "LOCMIN",
                                                  "ABSMIN",
                                                  "LOCMAX",
                                                  "ABSMAX",
                                                };

             /.
             Load kernels.
             ./
             furnsh_c( "gfrr_ex1.tm" );

             /.
             Store the time bounds of our search interval in
             the cnfine confinement window.
             ./
             str2et_c( "2007 JAN 01", &begtim );
             str2et_c( "2007 APR 01", &endtim );

             wninsd_c ( begtim, endtim, &cnfine );

             /.
             Search using a step size of 1 day (in units of seconds).
             The reference value is .3365 km/s. We're not using the
             adjustment feature, so we set 'adjust' to zero.
             ./
             step   = spd_c();
             adjust = 0.;
             refval = .3365;

             for ( j = 0;  j < NLOOPS;  j++ )
                {

                printf ( "Relation condition: %s \n",  relate[j] );

                /.
                Perform the search. The SPICE window 'result' contains
                the set of times when the condition is met.
                ./
                gfrr_c ( target,
                         abcorr,
                         obsrvr,
                         relate[j],
                         refval,
                         adjust,
                         step,
                         MAXWIN,
                         &cnfine,
                         &result );

                count = wncard_c( &result );

                /.
                Display the results.
                ./
                if (count == 0 )
                   {
                   printf ( "Result window is empty.\n\n" );
                   }
                else
                   {
                   for ( i = 0;  i < count;  i++ )
                      {

                      /.
                      Fetch the endpoints of the Ith interval
                      of the result window.
                      ./
                      wnfetd_c ( &result, i, &beg, &end );

                      timout_c ( beg, TIMFMT, TIMLEN, begstr );
                      timout_c ( end, TIMFMT, TIMLEN, endstr );

                      printf ( "Start time, drdt = %s \n", begstr );
                      printf ( "Stop time,  drdt = %s \n", endstr );

                      }

                   }

                printf("\n");

                }

             return( 0 );
             }

          When this program was executed on a Mac/Intel/cc/64-bit
          platform, the output was:

          Relation condition: =
          Start time, drdt = 2007-JAN-02 00:35:19.571
          Stop time,  drdt = 2007-JAN-02 00:35:19.571
          Start time, drdt = 2007-JAN-19 22:04:54.897
          Stop time,  drdt = 2007-JAN-19 22:04:54.897
          Start time, drdt = 2007-FEB-01 23:30:13.427
          Stop time,  drdt = 2007-FEB-01 23:30:13.427
          Start time, drdt = 2007-FEB-17 11:10:46.538
          Stop time,  drdt = 2007-FEB-17 11:10:46.538
          Start time, drdt = 2007-MAR-04 15:50:19.929
          Stop time,  drdt = 2007-MAR-04 15:50:19.929
          Start time, drdt = 2007-MAR-18 09:59:05.957
          Stop time,  drdt = 2007-MAR-18 09:59:05.957

          Relation condition: <
          Start time, drdt = 2007-JAN-02 00:35:19.571
          Stop time,  drdt = 2007-JAN-19 22:04:54.897
          Start time, drdt = 2007-FEB-01 23:30:13.427
          Stop time,  drdt = 2007-FEB-17 11:10:46.538
          Start time, drdt = 2007-MAR-04 15:50:19.929
          Stop time,  drdt = 2007-MAR-18 09:59:05.957

          Relation condition: >
          Start time, drdt = 2007-JAN-01 00:00:00.000
          Stop time,  drdt = 2007-JAN-02 00:35:19.571
          Start time, drdt = 2007-JAN-19 22:04:54.897
          Stop time,  drdt = 2007-FEB-01 23:30:13.427
          Start time, drdt = 2007-FEB-17 11:10:46.538
          Stop time,  drdt = 2007-MAR-04 15:50:19.929
          Start time, drdt = 2007-MAR-18 09:59:05.957
          Stop time,  drdt = 2007-APR-01 00:00:00.000

          Relation condition: LOCMIN
          Start time, drdt = 2007-JAN-11 07:03:58.991
          Stop time,  drdt = 2007-JAN-11 07:03:58.991
          Start time, drdt = 2007-FEB-10 06:26:15.441
          Stop time,  drdt = 2007-FEB-10 06:26:15.441
          Start time, drdt = 2007-MAR-12 03:28:36.404
          Stop time,  drdt = 2007-MAR-12 03:28:36.404

          Relation condition: ABSMIN
          Start time, drdt = 2007-JAN-11 07:03:58.991
          Stop time,  drdt = 2007-JAN-11 07:03:58.991

          Relation condition: LOCMAX
          Start time, drdt = 2007-JAN-26 02:27:33.762
          Stop time,  drdt = 2007-JAN-26 02:27:33.762
          Start time, drdt = 2007-FEB-24 09:35:07.812
          Stop time,  drdt = 2007-FEB-24 09:35:07.812
          Start time, drdt = 2007-MAR-25 17:26:56.148
          Stop time,  drdt = 2007-MAR-25 17:26:56.148

          Relation condition: ABSMAX
          Start time, drdt = 2007-MAR-25 17:26:56.148
          Stop time,  drdt = 2007-MAR-25 17:26:56.148
#### Restrictions
       1)  The kernel files to be used by this routine must be loaded
           (normally using the CSPICE routine furnsh_c) before this
           routine is called.

       2)  This routine has the side effect of re-initializing the
           range rate quantity utility package. Callers may themselves
           need to re-initialize the range rate quantity utility
           package after calling this routine.
#### Literature_References
       None.
#### Author_and_Institution
       N.J. Bachman        (JPL)
       J. Diaz del Rio     (ODC Space)
       E.D. Wright         (JPL)
#### Version
       -CSPICE Version 1.1.0, 01-NOV-2021 (JDR) (EDW)

           Added use of ALLOC_CHECK_INTRA to check net null effect on
           alloc count.

           Updated header to describe use of expanded confinement window.

           Edited the header to comply with NAIF standard.

           Updated the description of "nintvls", "cnfine" and "result"
           arguments.

           Added entries #4 and #5 and replaced former entry #6 by
           new entries #9 and #10 in -Exceptions section.

       -CSPICE Version 1.0.2, 31-JUL-2014 (EDW)

           Edit to header, replaced ' character with character " to indicate
           C strings.

           Edit to header, correct Required Reading entry eliminating ".REQ"
           suffix.

       -CSPICE Version 1.0.1, 28-FEB-2013 (NJB) (EDW)

           Header was updated to discuss use of gfstol_c.

           Edit to comments to correct search description.

           Edits to Example section, proper description of "standard.tm"
           meta kernel.

       -CSPICE Version 1.0.0, 26-AUG-2009 (EDW) (NJB)
#### Index_Entries
       GF range rate search
#### Link to routine gfrr_c source file gfrr_c.c

    Fri Dec 31 18:41:07 2021