Write a type 12 segment to an SPK file.
NAIF_IDS SPC SPK TIME
Variable I/O Description -------- --- -------------------------------------------------- handle I Handle of an SPK file open for writing. body I NAIF code for an ephemeris object. center I NAIF code for center of motion of body. frame I Reference frame name. first I Start time of interval covered by segment. last I End time of interval covered by segment. segid I Segment identifier. degree I Degree of interpolating polynomials. n I Number of states. states I Array of states. epoch0 I Epoch of first state in states array. step I Time step separating epochs of states. MAXDEG P Maximum allowed degree of interpolating polynomial.
handle is the file handle of an SPK file that has been opened for writing. body is the NAIF integer code for an ephemeris object whose state relative to another body is described by the segment to be created. center is the NAIF integer code for the center of motion of the object identified by body. frame is the NAIF name for a reference frame relative to which the state information for body is specified. first, last are, respectively, the start and stop times of the time interval over which the segment defines the state of body. segid is the segment identifier. An SPK segment identifier may contain up to 40 characters. degree is the degree of the Hermite polynomials used to interpolate the states. All components of the state vectors are interpolated by polynomials of fixed degree. n is the number of states in the input state vector array. states contains a time-ordered array of geometric states ( x, y, z, dx/dt, dy/dt, dz/dt, in kilometers and kilometers per second ) of body relative to center, specified relative to frame. epoch0 is the epoch corresponding to the first state in the state array. Because extra states are needed at the beginning and end of the segment in order for the interpolation method to work, epoch0 will normally precede first. step is the time step separating the epochs of adjacent states in the input state array. step is specified in seconds.
None. See $Particulars for a description of the effect of this routine.
MAXDEG is the maximum allowed degree of the interpolating polynomial. If the value of MAXDEG is increased, the SPICELIB routine SPKPVN must be changed accordingly. In particular, the size of the record passed to SPKRnn and SPKEnn must be increased, and comments describing the record size must be changed.
This routine writes an SPK type 12 data segment to the open SPK file according to the format described in the type 12 section of the SPK Required Reading. The SPK file must have been opened with write access.
Suppose that you have states and are prepared to produce a segment of type 12 in an SPK file. The following code fragment could be used to add the new segment to a previously opened SPK file attached to handle. The file must have been opened with write access. #include "SpiceUsr.h" . . . /. Create a segment identifier. ./ #define SEGID "MY_SAMPLE_SPK_TYPE_12_SEGMENT" /. Write the segment. ./ spkw12_c ( handle, body, center, frame, first, last, segid, degree, n, states, epoch0, step );
If any of the following exceptions occur, this routine will return without creating a new segment. 1) If frame is not a recognized name, the error SPICE(INVALIDREFFRAME) is signaled. 2) If the last non-blank character of segid occurs past index 40, the error SPICE(SEGIDTOOLONG) is signaled. 3) If segid contains any nonprintable characters, the error SPICE(NONPRINTABLECHARS) is signaled. 4) If degree is not at least 1 or is greater than MAXDEG, the error SPICE(INVALIDDEGREE) is signaled. 5) If degree is not odd, the error SPICE(INVALIDDEGREE) is signaled. 6) If the number of states n is not at least (degree+1)/2, the error SPICE(TOOFEWSTATES) will be signaled. 7) If first is greater than or equal to last then the error SPICE(BADDESCRTIMES) will be signaled. 8) If step is non-positive, the error SPICE(INVALIDSTEPSIZE) will be signaled. 9) If the first epoch epoch0 is greater than first, the error SPICE(BADDESCRTIMES) will be signaled. 10) If the last epoch first + (n-1)*step is less than last, the error SPICE(BADDESCRTIMES) will be signaled. 11) If either the input frame or segment ID string pointer is null, the error SPICE(NULLPOINTER) is signaled. 12) If either the input frame or segment ID string is empty, the error SPICE(EMPTYSTRING) is signaled.
A new type 12 SPK segment is written to the SPK file attached to HANDLE.
N.J. Bachman (JPL)
-CSPICE Version 1.0.0, 23-FEB-2000 (NJB)
write spk type_12 ephemeris data segment