CSPICE_WNEXTD extracts the left or right endpoints from a double precision window. For important details concerning this module's function, please refer to the CSPICE routine wnextd_c.
Given: side a scalar character that indicates whether the left or right endpoints of the intervals in the window are to be extracted. 'L', 'l' Left endpoints. 'R', 'r' Right endpoints. If 'side' is not recognized, the input window is not changed. window a scalar, double precision window containing zero or more intervals. 'window' must be created as a window structure via a cspice_celld call. the call: cspice_wnextd, side, window returns: window on output, is the collection of singleton intervals containing either the left or the right endpoints of the intervals in the original window.
Any 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. ;; ;; Create a cell containing a double ;; precision 8-vector. ;; win1 = cspice_celld( 8 ) ;; ;; Define a window with four intervals. ;; darray = [ [ 1.d, 3.0], [ 7.0, 11.0], [23.0, 27.0], [29.d, 29.d] ] ;; ;; Add the window data to the cell. ;; for i=0, 3 do begin cspice_wninsd, darray[0,i], darray[1,i], win1 endfor ;; ;; Extract left endpoints: ;; cspice_wnextd, 'L', win1 ;; ;; Calculate the number of intervals in the ;; return window 'win1'. ;; no_intervals = cspice_wncard(win1) ;; ;; Output the intervals. ;; for i= 0, (no_intervals -1 ) do begin cspice_wnfetd, win1, i, left, right print, left, right endfor IDL outputs: 1.0000000 1.0000000 7.0000000 7.0000000 23.000000 23.000000 29.000000 29.000000
The user must create any needed window structures with cspice_celld prior to use regardless of whether the routine uses the window as input or returns it as output.
-Icy Version 1.0.2, 26-NOV-2007, EDW (JPL) Implemented use of cspice_wncard function to return window cardinality. -Icy Version 1.0.1, 12-SEP-2006, EDW (JPL) Correct Required Reading citation CELL.REQ to CELLS.REQ. -Icy Version 1.0.0, 08-AUG-2004, EDW (JPL)
extract the endpoints from a d.p. window
Wed Apr 5 17:58:05 2017