Table of contents
CSPICE_WNCOND contracts each of the intervals of a double
precision window.
Given:
left amount to add to each left interval endpoint in the input
`window'.
[1,1] = size(left); double = class(left)
right amount to subtract to each right interval endpoint in the
input `window'.
[1,1] = size(right); double = class(right)
window SPICE window containing zero or more intervals.
[2m,1] = size(window); double = class(window)
the call:
[window_f] = cspice_wncond( left, right, window )
returns:
window_f SPICE window containing zero or more intervals, representing
the original `window' with each of its intervals contracted
by `left' units on the left and `right' units on the right
[2n,1] = size(window_f); double = class(window_f)
`window_f' can overwrite `window'.
None.
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.
1) Given a double precision window, containing the following four
intervals:
[ 1.0, 3.0 ], [ 7.0, 11.0 ], [ 23.0, 27.0 ], [ 29.0, 29.0 ]
contract each interval by 2.0 units on the left and 1.0 on the
right endpoints, then by -2.0 units on the left and 2.0 units on
the right, and finally -2.0 units on the left and -1.0 units on
the right.
Example code begins here.
function wncond_ex1()
%
% Let `window' contain the intervals
%
window = [ [ 1; 3 ]; [ 7; 11 ]; [ 23; 27 ]; [ 29; 29 ]; ];
%
% Apply the following series of calls:
%
window = cspice_wncond( 2, 1, window );
fprintf( '1: Contracted window by 2 (left) and 1 (right)\n' );
for i=1:cspice_wncard(window)
[left, right] = cspice_wnfetd( window, i );
fprintf( '%16.6f %16.6f\n', left, right );
end
window = cspice_wncond( -2, 2, window );
fprintf( '2: Contracted window by -2 (left) and 2 (right)\n' );
for i=1:cspice_wncard(window)
[left, right] = cspice_wnfetd( window, i );
fprintf( '%16.6f %16.6f\n', left, right );
end
window = cspice_wncond( -2, -1, window );
fprintf( '3: Contracted window by -2 (left) and -1 (right)\n' );
for i=1:cspice_wncard(window)
[left, right] = cspice_wnfetd( window, i );
fprintf( '%16.6f %16.6f\n', left, right );
end
When this program was executed on a Mac/Intel/Octave6.x/64-bit
platform, the output was:
1: Contracted window by 2 (left) and 1 (right)
9.000000 10.000000
25.000000 26.000000
2: Contracted window by -2 (left) and 2 (right)
7.000000 8.000000
23.000000 24.000000
3: Contracted window by -2 (left) and -1 (right)
5.000000 9.000000
21.000000 25.000000
Note that intervals may be "contracted" by negative amounts.
In the example above, the second case shifts each interval to
the left, while the third case undoes the effect of the first
call (without restoring the destroyed intervals).
Note also that the third case is exactly equivalent to the
call:
cspice_wnexpd( 2, 1, window )
This routine contracts (shortens) each of the intervals in
the input window. The adjustments are not necessarily symmetric.
That is, left units are added to the left endpoint of each
interval, and right units are subtracted from the right endpoint
of each interval, where left and right may be different.
Intervals are dropped when they are contracted by amounts
greater than their measures.
1) 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.
2) If any of the input arguments, `left', `right' or `window', is
undefined, an error is signaled by the Matlab error handling
system.
3) If any of the input arguments, `left', `right' or `window', is
not of the expected type, or it does not have the expected
dimensions and size, an error is signaled by the Mice
interface.
None.
None.
MICE.REQ
WINDOWS.REQ
None.
J. Diaz del Rio (ODC Space)
S.C. Krening (JPL)
E.D. Wright (JPL)
-Mice Version 1.1.0, 10-AUG-2021 (EDW) (JDR)
Edited the header to comply with NAIF standard. Added
example's problem statement and reformatted example's output.
Added -Parameters, -Exceptions, -Files, -Restrictions,
-Literature_References and -Author_and_Institution sections, and
completed -Particulars section.
Eliminated use of "lasterror" in rethrow.
Removed reference to the function's corresponding CSPICE header from
-Required_Reading section.
-Mice Version 1.0.1, 12-MAR-2012 (EDW) (SCK)
Edited -I/O section to conform to NAIF standard for Mice documentation.
-Mice Version 1.0.0, 24-JUL-2007 (EDW)
contract the intervals of a d.p. window
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