Table of contents
CSPICE_DSKOPN opens a new DSK file, returning the handle
of the opened file.
Given:
fname the name of the DSK file to open.
[1,c1] = size(fname); char = class(fname)
or
[1,1] = size(fname); cell = class(fname)
ifname the descriptive internal filename for the DSK.
[1,c2] = size(ifname); char = class(ifname)
or
[1,1] = size(ifname); cell = class(ifname)
ncomch the scalar integer number of characters to
reserve for comments.
[1,1] = size(ncomch); int32 = class(ncomch)
the call:
handle = cspice_dskopn( name, ifname, ncomch )
returns:
handle the file handle assigned to 'fname'.
[1,1] = size(handle); int32 = class(handle)
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) Create a three-segment DSK file using plate model data for
Phobos. Use latitudinal, rectangular, and planetodetic
coordinates in the respective segments. This is not a
realistic example, but it serves to demonstrate use of
the supported coordinate systems.
Use the DSK kernel below to provide, for simplicity, the input
plate and vertex data. This file has one segment only.
phobos_3_3.bds
Example code begins here.
function dskopn_ex1()
%
% MiceUser globally defines DSK parameters.
% For more information, please see MiceDSK.m.
%
MiceUser
NSEG = 3;
cornam = { 'radius', 'Z-coordinate', 'Z-coordinate', 'altitude'};
%
% Assign names of input and output DSK files.
%
indsk = 'phobos_3_3.bds';
dsk = 'phobos_3_3_3seg.bds';
if ( exist( dsk, 'file' ) == 2 )
delete( dsk )
end
%
% Open input DSK for read access; find first segment.
%
inhan = cspice_dasopr( indsk );
[dladsc, found] = cspice_dlabfs( inhan );
%
% Fetch vertices and plates from input DSK file.
%
% Note that vertex and plate indices are 1-based.
%
disp( 'Reading input data...' )
vrtces = cspice_dskv02( inhan, dladsc, 1, SPICE_DSK02_MAXVRT );
plates = cspice_dskp02( inhan, dladsc, 1, SPICE_DSK02_MAXPLT );
disp( 'Done.' )
%
% Set input array sizes required by cspice_dskmi2.
%
voxpsz = SPICE_DSK02_MAXVXP;
voxlsz = SPICE_DSK02_MXNVLS;
worksz = SPICE_DSK02_MAXCEL;
spaisz = SPICE_DSK02_SPAISZ;
makvtl = true;
%
% Set fine and coarse voxel scales. (These usually
% need to determined by experimentation.)
%
finscl = 5.0;
corscl = 4;
%
% Open a new DSK file.
%
handle = cspice_dskopn( dsk, dsk, 0 );
for segno=1:NSEG
%
% Create spatial index. We won't generate a
% vertex-plate mapping, so we set the flag
% for creating this map to "false."
%
fprintf( 'Creating segment %d\n', segno )
fprintf( 'Creating spatial index...\n' )
[spaixd, spaixi] = cspice_dskmi2( vrtces, plates, finscl, ...
corscl, worksz, voxpsz, ...
voxlsz, makvtl, ...
spaisz );
fprintf( 'Done.\n')
%
% Set up inputs describing segment attributes:
%
% - Central body: Phobos
% - Surface ID code: user's choice.
% We use the segment number here.
% - Data class: general (arbitrary) shape
% - Body-fixed reference frame
% - Time coverage bounds (TBD)
%
center = 401;
surfid = segno;
dclass = SPICE_DSK_GENCLS;
frame = 'IAU_PHOBOS';
first = -50. * cspice_jyear();
last = 50. * cspice_jyear();
%
% Set the coordinate system and coordinate system
% bounds based on the segment index.
%
% Zero out the coordinate parameters to start.
%
corpar = zeros(SPICE_DSK_NSYPAR,1);
switch segno
case 1
%
% Use planetocentric latitudinal coordinates. Set
% the longitude and latitude bounds.
%
corsys = SPICE_DSK_LATSYS;
mncor1 = -cspice_pi();
mxcor1 = cspice_pi();
mncor2 = -cspice_halfpi();
mxcor2 = cspice_halfpi();
case 2
%
% Use rectangular coordinates. Set the
% X and Y bounds.
%
% The bounds shown here were derived from
% the plate data. They lie slightly outside
% of the range spanned by the plates.
%
corsys = SPICE_DSK_RECSYS;
mncor1 = -1.3;
mxcor1 = 1.31;
mncor2 = -1.21;
mxcor2 = 1.2;
case 3
%
% Set the coordinate system to planetodetic.
%
corsys = SPICE_DSK_PDTSYS;
mncor1 = -cspice_pi();
mxcor1 = cspice_pi();
mncor2 = -cspice_halfpi();
mxcor2 = cspice_halfpi();
%
% We'll use equatorial and polar radii from
% pck00010.tpc. These normally would be fetched
% at run time, but for simplicity, we'll use
% hard-coded values.
%
re = 13.0;
rp = 9.1;
f = ( re - rp ) / re;
corpar = [ re, f ]';
otherwise
error( 'Mice(BUG)' )
end
%
% Compute plate model radius bounds.
%
fprintf( 'Computing %s bounds of plate set...\n', ...
char(cornam(corsys)) )
[mncor3, mxcor3] = cspice_dskrb2( vrtces, plates, ...
corsys, corpar );
fprintf ( 'Done.\n' )
%
% Write the segment to the file.
%
fprintf( 'Writing segment...\n' )
cspice_dskw02( handle, center, surfid, dclass, frame, ...
corsys, corpar, mncor1, mxcor1, mncor2, ...
mxcor2, mncor3, mxcor3, first, last, ...
vrtces, plates, spaixd, spaixi )
end
%
% Close the input DSK.
%
cspice_dascls( inhan )
cspice_dskcls( handle, true )
When this program was executed on a Mac/Intel/Octave6.x/64-bit
platform, the output was:
Reading input data...
Done.
Creating segment 1
Creating spatial index...
Done.
Computing radius bounds of plate set...
Done.
Writing segment...
Creating segment 2
Creating spatial index...
Done.
Computing Z-coordinate bounds of plate set...
Done.
Writing segment...
Creating segment 3
Creating spatial index...
Done.
Computing altitude bounds of plate set...
Done.
Writing segment...
Note that after run completion, a new DSK exists in the output
directory.
A cspice_dskcls call should balance every cspice_dskopn
call.
1) If the input filename is blank, an error is signaled by a
routine in the call tree of this routine. No file will be
created.
2) If the specified file cannot be opened without exceeding the
maximum allowed number of open DAS files, an error is signaled
by a routine in the call tree of this routine. No file will be
created.
3) If the file cannot be opened properly, an error is signaled by
a routine in the call tree of this routine. No file will be
created.
4) If the initial records in the file cannot be written, an error
is signaled by a routine in the call tree of this routine. No
file will be created.
5) If no logical units are available, an error is signaled by a
routine in the call tree of this routine. No file will be
created.
6) If the internal file name contains nonprinting characters
(ASCII codes decimal 0-31 and 127-255), an error is signaled
by a routine in the call tree of this routine. No file will be
created.
7) If the number of comment characters allocated `ncomch' is
negative, an error is signaled by a routine in the call
tree of this routine. No file will be created.
8) If any of the input arguments, `fname', `ifname' or `ncomch',
is undefined, an error is signaled by the Matlab error
handling system.
9) If any of the input arguments, `fname', `ifname' or `ncomch',
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'.
None.
MICE.REQ
DAS.REQ
DSK.REQ
None.
N.J. Bachman (JPL)
J. Diaz del Rio (ODC Space)
E.D. Wright (JPL)
-Mice Version 1.1.0, 10-AUG-2021 (EDW) (JDR)
Edited the -Examples section to comply with NAIF standard.
Added -Parameters, -Exceptions, -Files, -Restrictions,
-Literature_References and -Author_and_Institution sections.
Eliminated use of "lasterror" in rethrow.
Removed reference to the function's corresponding CSPICE header from
-Required_Reading section.
-Mice Version 1.0.0, 02-FEB-2016 (EDW) (NJB)
open a new DSK file
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