wnfetd_c |

Table of contents## Procedurewnfetd_c ( Fetch an interval from a DP window ) void wnfetd_c ( SpiceCell * window, SpiceInt n, SpiceDouble * left, SpiceDouble * right ) ## AbstractFetch a particular interval from a double precision window. ## Required_ReadingWINDOWS ## KeywordsWINDOWS ## Brief_I/OVARIABLE I/O DESCRIPTION -------- --- -------------------------------------------------- window I Input window. n I Index of interval to be fetched. left, right O Left, right endpoints of the nth interval. ## Detailed_Inputwindow is a window containing zero or more intervals. `window' must be declared as a double precision SpiceCell. CSPICE provides the following macro, which declares and initializes the cell SPICEDOUBLE_CELL ( window, WINDOWSZ ); where WINDOWSZ is the maximum capacity of `window'. n is the index of a particular interval within the window. Indices range from 0 to NINT-1, where NINT is the number of intervals in the window (card_c(&window)/2). ## Detailed_Outputleft, right are the left and right endpoints of the N'th interval in the input window. If the interval is not found, `left' and `right' are not defined. ## ParametersNone. ## Exceptions1) If `n' is less than one, the error SPICE(NOINTERVAL) is signaled by a routine in the call tree of this routine. 2) If the interval does not exist, i.e. n > card_c(window)/2, the error SPICE(NOINTERVAL) is signaled by a routine in the call tree of this routine. 3) The cardinality of the input `window' must be even. Left endpoints of stored intervals must be strictly greater than preceding right endpoints. Right endpoints must be greater than or equal to corresponding left endpoints. Invalid window data are not diagnosed by this routine and may lead to unpredictable results. 4) If the `window' cell argument has a type other than SpiceDouble, the error SPICE(TYPEMISMATCH) is signaled. ## FilesNone. ## ParticularsNone. ## ExamplesThe 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) The following code example demonstrates how to insert an interval into an existing double precision SPICE window, and how to loop over all its intervals to extract their left and right points. Example code begins here. /. Program wnfetd_ex1 ./ #include <stdio.h> #include "SpiceUsr.h" int main() { /. Local parameters. ./ #define WNSIZE 10 /. Local variables. ./ SpiceDouble left; SpiceDouble right; SPICEDOUBLE_CELL ( window, WNSIZE ); SpiceInt i; /. Validate the window with size WNSIZE and zero elements. ./ wnvald_c ( WNSIZE, 0, &window ); /. Insert the intervals [ 1, 3 ] [ 7, 11 ] [ 23, 27 ] into `window'. ./ wninsd_c ( 1.0, 3.0, &window ); wninsd_c ( 7.0, 11.0, &window ); wninsd_c ( 23.0, 27.0, &window ); /. Loop over the number of intervals in `window', output the `left' and `right' endpoints for each interval. ./ for ( i=0; i<wncard_c(&window); i++) { ## RestrictionsNone. ## Literature_ReferencesNone. ## Author_and_InstitutionN.J. Bachman (JPL) J. Diaz del Rio (ODC Space) W.L. Taber (JPL) I.M. Underwood (JPL) E.D. Wright (JPL) ## Version-CSPICE Version 1.0.2, 10-AUG-2021 (JDR) Edited the header to comply to NAIF standard. Added complete code example, problem statement and solution. Extended description of argument "window" in -Detailed_Input to include type and preferred declaration method. Added entry #3 in -Exceptions section. -CSPICE Version 1.0.1, 30-JUL-2007 (EDW) Removed erroneous description in the -Examples section indicating "Undefined" as a return state after an error event caused by an invalid value of n. -CSPICE Version 1.0.0, 22-AUG-2002 (NJB) (WLT) (IMU) ## Index_Entriesfetch an interval from a d.p. window |

Fri Dec 31 18:41:15 2021