Procedure

   void gfsstp_c ( SpiceDouble  step ) 

Abstract

 
   Set the step size to be returned by gfstep_c.
 

Required_Reading

 
   GF
   TIME

Keywords

   GEOMETRY 
   SEARCH 
   UTILITY 
 

Brief_I/O

 
   VARIABLE  I/O  DESCRIPTION 
   --------  ---  -------------------------------------------------- 
   step       I   Time step to take. 
 

Detailed_Input

 
   step      is the output step size to be returned by the next call 
             to gfstep_c. Units are TDB seconds. 
 
             `step' is used in the GF search root-bracketing process.
             `step' indicates how far to advance the gfstep_c input
             argument `time' so that `time' and time+step may bracket a
             state transition and definitely do not bracket more than
             one state transition.
 

Detailed_Output

 
   None. 
 

Parameters

 
   None. 
 

Exceptions

 
   1) If the input step size is non-positive, the error 
      SPICE(INVALIDSTEP) is signaled. The stored step value  
      is not updated. 
 

Files

 
   None. 
 

Particulars

 
   This routine sets the step size to be returned by the
   next call to gfstep_c.
 

Examples

 

   1) User applications can pass gfstep_c to mid-level GF API routines 
      expecting a step size routine as an input argument. Before such
      a call is made, the value of the step to be returned by gfstep_c
      must be set via a call to this routine.

      For example, the GF API routine gfocce_c can be called as shown 
      in the code fragment below.
      
            /.
            Select a twenty-second step. We'll ignore any occultations
            lasting less than 20 seconds.
            ./
            step = 20.0;
            gfsstp_c ( step );

            /.
            Perform the search.
            ./
            gfocce_c ( "ANY",                            
                       "MOON",     "ellipsoid",  "IAU_MOON", 
                       "SUN",      "ellipsoid",  "IAU_SUN",  
                       "LT",       "EARTH",      CNVTOL,    
                       gfstep_c,   gfrefn_c,     rpt,       
                       gfrepi_c,   gfrepu_c,     gfrepf_c, 
                       bail,       gfbail_c,     cnfine,   
                       &result                              );   
 

Restrictions

 
   None.
 

Literature_References

 
   None. 
 

Author_and_Institution

 
   N.J. Bachman   (JPL)
   W.L. Taber     (JPL) 
   I.M. Underwood (JPL) 
   L.S. Elson     (JPL) 
   E.D. Wright    (JPL)  
 

Version

 
   -CSPICE Version 2.0.1, 15-APR-2009 (LSE) (NJB)

Index_Entries

 
   GF set constant step size

Link to routine gfsstp_c source file gfsstp_c.c