Table of contents
CSPICE_DAFOPR opens a DAF for subsequent read requests.
Given:
fname the string name of a DAF to open for read (search) access.
[1,c1] = size(fname); char = class(fname)
or
[1,1] = size(fname); cell = class(fname)
the call:
[handle] = cspice_dafopr( fname )
returns:
handle the file handle used by other DAF routines
to refer to `fname'.
[1,1] = size(handle); int32 = class(handle)
Use cspice_dafcls to close files opened by this routine.
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) Use a simple routine to output the double precision and integer
values stored in an SPK's segments descriptors. This function
opens a DAF for read, performs a forwards search for the DAF
arrays, prints segments description for each array found, then
closes the DAF.
Use the SPK kernel below as input DAF file for the program.
de421.bsp
Example code begins here.
function dafopr_ex1()
%
% Local constants
%
kernel = 'de421.bsp';
%
% Open a DAF for read. Return a `handle' referring to the file.
%
handle = cspice_dafopr( kernel );
%
% Define the summary parameters appropriate
% for an SPK file.
%
ND = 2;
NI = 6;
%
% Begin a forward search on the file.
%
cspice_dafbfs( handle );
%
% Search until a DAF array is found.
%
found = cspice_daffna;
%
% Loop while the search finds subsequent DAF arrays.
%
while found
[dc, ic ] = cspice_dafgs( ND, NI );
fprintf( 'Doubles: ' )
fprintf( '%f ', dc )
fprintf( '\n' )
fprintf( 'Integers: ' )
fprintf( '%d ', ic )
fprintf( '\n\n' )
%
% Check for another segment.
%
found = cspice_daffna;
end
%
% Safely close the DAF.
%
cspice_dafcls( handle )
When this program was executed on a Mac/Intel/Octave6.x/64-bit
platform, the output was:
Doubles: -3169195200.000000 1696852800.000000
Integers: 1 0 1 2 641 310404
Doubles: -3169195200.000000 1696852800.000000
Integers: 2 0 1 2 310405 423048
Doubles: -3169195200.000000 1696852800.000000
Integers: 3 0 1 2 423049 567372
Doubles: -3169195200.000000 1696852800.000000
Integers: 4 0 1 2 567373 628976
Doubles: -3169195200.000000 1696852800.000000
Integers: 5 0 1 2 628977 674740
Doubles: -3169195200.000000 1696852800.000000
Integers: 6 0 1 2 674741 715224
Doubles: -3169195200.000000 1696852800.000000
Integers: 7 0 1 2 715225 750428
Doubles: -3169195200.000000 1696852800.000000
Integers: 8 0 1 2 750429 785632
Doubles: -3169195200.000000 1696852800.000000
Integers: 9 0 1 2 785633 820836
Doubles: -3169195200.000000 1696852800.000000
Integers: 10 0 1 2 820837 944040
Doubles: -3169195200.000000 1696852800.000000
Integers: 301 3 1 2 944041 1521324
Doubles: -3169195200.000000 1696852800.000000
Integers: 399 3 1 2 1521325 2098608
Doubles: -3169195200.000000 1696852800.000000
Integers: 199 1 1 2 2098609 2098620
Doubles: -3169195200.000000 1696852800.000000
Integers: 299 2 1 2 2098621 2098632
Doubles: -3169195200.000000 1696852800.000000
Integers: 499 4 1 2 2098633 2098644
Note, the specific contents of `ic' and `dc' depend on the
type of DAF.
Note, the final entries in the integer array contain the segment
start/end indexes. The output indicates the search proceeded
from the start of the file (low value index) towards the end
(high value index).
Most DAFs require only read access. If you do not need to
change the contents of a file, you should open it with cspice_dafopr.
1) If the specified file has already been opened for read
access, the handle already associated with the file is
returned.
2) If the specified file has already been opened for write
access, an error is signaled by a routine in the call
tree of this routine.
3) If the specified file has already been opened by a non-DAF
routine, an error is signaled by a routine in the call
tree of this routine.
4) If the specified file cannot be opened without exceeding
the maximum number of files, the error SPICE(DAFFTFULL)
is signaled by a routine in the call tree of this routine.
5) If the attempt to read the file's file record fails, the error
SPICE(FILEREADFAILED) is signaled by a routine in the call
tree of this routine.
6) If the specified file is not a DAF file, an error is
signaled by a routine in the call tree of this routine.
7) If no logical units are available, an error is
signaled by a routine in the call tree of this routine.
8) If the file does not exist, an error is signaled by a routine
in the call tree of this routine.
9) If an i/o error occurs in the process of opening the file,
the error is signaled by a routine in the call tree of this
routine.
10) If the file name is blank or otherwise inappropriate,
an error is signaled by a routine in the call tree of this
routine.
11) If the file was transferred improperly via FTP, an error is
signaled by a routine in the call tree of this routine.
12) If the file utilizes a binary file format that is not
currently supported on this platform, an error is signaled by
a routine in the call tree of this routine.
13) If the input argument `fname' is undefined, an error is
signaled by the Matlab error handling system.
14) If the input argument `fname' is not of the expected type, or
it does not have the expected dimensions and size, an error is
signaled by the Mice interface.
See argument `fname'.
1) Files opened using this routine must be closed with cspice_dafcls.
MICE.REQ
DAF.REQ
None.
J. Diaz del Rio (ODC Space)
E.D. Wright (JPL)
-Mice Version 1.1.0, 10-AUG-2021 (EDW) (JDR)
Added -Parameters, -Exceptions, -Files, -Restrictions,
-Literature_References and -Author_and_Institution sections.
Edits to the -Examples section to comply with NAIF standard.
Modified code example to hardcode SPK file to be used as input.
Eliminated use of "lasterror" in rethrow.
Removed reference to the function's corresponding CSPICE header from
-Required_Reading section.
-Mice Version 1.0.0, 10-JUL-2012 (EDW)
open DAF for read
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