CSPICE_WNEXPD expands each of the intervals of a double
precision window.
For important details concerning this module's function, please refer to
the CSPICE routine wnexpd_c.
Given:
left the scalar, double precision amount to subtract
from the left endpoint of each interval in the input
window.
right the scalar, double precision amount to add
to the right endpoint of each interval in the window.
window a window containing zero or more intervals.
'window' must be created as a window structure via
a cspice_celld call.
the call:
cspice_wnexpd, left, right, window
returns:
window on output, is the original window with each of its
intervals expanded by 'left' units on the left and
'right' units on the right.
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 8vector.
;;
win1 = cspice_celld( 8 )
;;
;; Define a window with four intervals.
;;
darray = [ [ 1.d, 3.0], [ 7.0, 11.0], [23.0, 27.0], [29.0, 29.0] ]
;;
;; Add the window data to the cell.
;;
for i=0, 3 do begin
cspice_wninsd, darray[0,i], darray[1,i], win1
endfor
;;
;; Perform the expansion.
;;
left = 2.d
right = 1.d
cspice_wnexpd, left, right, 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 4.0000000
5.0000000 12.000000
21.000000 30.000000
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.REQ
CELLS.REQ
WINDOWS.REQ
Icy Version 1.0.2, 26NOV2007, EDW (JPL)
Implemented use of cspice_wncard function to return
window cardinality.
Icy Version 1.0.1, 12SEP2006, EDW (JPL)
Correct Required Reading citation CELL.REQ to CELLS.REQ.
Icy Version 1.0.0, 08AUG2004, EDW (JPL)
expand the intervals of a d.p. window
