Table of contents
CSPICE_DLAENS ends a new segment in a DLA file.
Given:
handle the integer handle associated with the DLA file to be
updated.
[1,1] = size(handle); int32 = class(handle)
This handle is used to identify the file in subsequent
calls to other DLA or DAS routines.
The DLA file must be open for write access. A new DLA
segment is completed in the indicated file. The file
is left open, since data may be written to the file
following a call to this routine.
the call:
cspice_dlaens( handle )
returns:
None. See the -Particulars and -Examples header sections for
a description of the actions performed 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) Create a DLA file containing one segment; the segment
contains character, double precision, and integer data.
After writing and closing the file, open the file for
read access; dump the data to standard output.
Example code begins here.
function dlaens_ex1()
%
% MiceUser is a file that makes certain variables global.
% You must call MiceUser to have access to the parameters used
% in this example.
%
MiceUser;
%
% Local parameters
%
DLA = 'dlaens_ex1.dla';
LNSIZE = 61;
MAXC = 5;
MAXD = 50;
MAXI = 100;
%
% Local variables
%
dvals = zeros( MAXD, 1 );
ivals = zeros( MAXI, 1, 'int32' );
cvals = zeros( MAXC, LNSIZE, 'uint8' );
cvals2 = zeros( MAXC, LNSIZE, 'uint8' );
%
% Set the internal file name. Don't reserve characters in
% the DAS comment area.
%
ifname = 'Example DLA file for testing';
ncomch = 0;
%
% Open a new DLA file.
%
[handle] = cspice_dlaopn( DLA, 'DLA', ifname, ncomch );
%
% Begin a new segment.
%
cspice_dlabns( handle );
%
% Add character data to the segment.
%
for i=1:MAXC
for j=1:LNSIZE
k = mod( j+i-1, 10 );
cvals(i,j) = uint8('0') + k;
end
end
cspice_dasadc( handle, MAXC*LNSIZE, 1, LNSIZE, cvals );
%
% Add integer and double precision data to the segment.
%
for i=1:MAXI
ivals(i) = i;
end
cspice_dasadi( handle, ivals );
for i=1:MAXD
dvals(i) = double(i);
end
cspice_dasadd( handle, dvals );
%
% End the segment.
%
cspice_dlaens( handle );
%
% Close the file. The routine cspice_dascls flushes the DAS
% buffers and segregates the file before closing it.
%
cspice_dascls( handle );
%
% Now read the file and check the data.
%
[handle] = cspice_dasopr( DLA );
%
% Obtain the segment descriptor for the sole segment
% in the file. We need not check the found flag
% in this case because we know there is one segment
% in the file.
%
[descr, found] = cspice_dlabfs( handle );
%
% Fetch character data from the segment. Obtain the
% base address of the character data and the
% character count from the descriptor.
%
base = descr(SPICE_DLA_CBSIDX);
n = descr(SPICE_DLA_CSZIDX);
[cvals2] = cspice_dasrdc( handle, base+1, base+n, ...
1, LNSIZE, cvals2 );
%
% Display the character data.
%
fprintf( '\n' )
fprintf( 'Character array:\n' )
cvals2 = cellstr(char(cvals2));
for i=1:n/LNSIZE
fprintf( '%s\n', char(cvals2(i)) )
end
%
% Fetch and display the integer and double precision data.
%
base = descr(SPICE_DLA_IBSIDX);
n = descr(SPICE_DLA_ISZIDX);
[ivals2] = cspice_dasrdi( handle, base+1, base+n );
fprintf( '\n' )
fprintf( 'Integer array:\n' )
for i=0:n/10-1
for j=1:10
fprintf( '%6d', ivals2(i*10+j) )
end
fprintf( '\n' )
end
base = descr(SPICE_DLA_DBSIDX);
n = descr(SPICE_DLA_DSZIDX);
[dvals2] = cspice_dasrdd( handle, base+1, base+n );
fprintf( '\n' )
fprintf( 'Double precision array:\n' )
for i=0:n/10-1
for j=1:10
fprintf( '%6.1f', dvals2(i*10+j) )
end
fprintf( '\n' )
end
%
% Close the file. This step is unnecessary in this
% program, but is a good practice in general
% because closing the file frees resources.
%
cspice_dascls( handle );
When this program was executed on a Mac/Intel/Octave6.x/64-bit
platform, the output was:
Character array:
1234567890123456789012345678901234567890123456789012345678901
2345678901234567890123456789012345678901234567890123456789012
3456789012345678901234567890123456789012345678901234567890123
4567890123456789012345678901234567890123456789012345678901234
5678901234567890123456789012345678901234567890123456789012345
Integer array:
1 2 3 4 5 6 7 8 9 10
11 12 13 14 15 16 17 18 19 20
21 22 23 24 25 26 27 28 29 30
31 32 33 34 35 36 37 38 39 40
41 42 43 44 45 46 47 48 49 50
51 52 53 54 55 56 57 58 59 60
61 62 63 64 65 66 67 68 69 70
71 72 73 74 75 76 77 78 79 80
81 82 83 84 85 86 87 88 89 90
91 92 93 94 95 96 97 98 99 100
Double precision array:
1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0
11.0 12.0 13.0 14.0 15.0 16.0 17.0 18.0 19.0 20.0
21.0 22.0 23.0 24.0 25.0 26.0 27.0 28.0 29.0 30.0
31.0 32.0 33.0 34.0 35.0 36.0 37.0 38.0 39.0 40.0
41.0 42.0 43.0 44.0 45.0 46.0 47.0 48.0 49.0 50.0
Note that after run completion, a new DLA file exists in the
output directory.
DLA files are built using the DAS low-level format; DLA files are
a specialized type of DAS file in which data are organized as a
doubly linked list of segments. Each segment's data belong to
contiguous components of character, double precision, and integer
type.
This routine supports creation of a DLA segment. DLA segments
are created by appending data to the DAS integer, double
precision, and character address spaces of a DLA file. The new
segment's descriptor is located immediately before the integer
component of the segment's data.
When a new segment is added to a DLA file, the segment is
inserted into the file's doubly linked segment list. If the new
segment is the first, the DLA file's first and last list entry
pointers are updated to point to the new segment; specifically,
these pointers point to the first integer of the new segment's
descriptor. The backward pointer of the new segment is set to
null in this case.
If the new segment is not the first, the DLA file's list end
pointer is updated to point to the new segment, and the forward
pointer of the previous segment also is updated to point to the
first integer of the new segment's descriptor. The backward
pointer of the new segment points to to point to the first
integer of the previous segment's descriptor.
The normal sequence of operations required to create a DLA
segment is as follows:
Call cspice_dlaopn to create a new, empty DLA file.
For each segment to be created,
Call cspice_dlabns to begin a segment.
Use the DAS "add" and "update" routines to populate
the segment with data.
Call cspice_dlaens to end the segment.
Call cspice_dascls to segregate and close the DLA file.
1) If the input file handle does not refer to a DAS file that is
open for write access, an error is signaled by a routine
in the call tree of this routine.
2) If an error occurs while reading or writing to the DLA file,
the error is signaled by a routine in the call tree of
this routine.
3) If the input argument `handle' is undefined, an error is
signaled by the Matlab error handling system.
4) If the input argument `handle' 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 description of input argument `handle'.
None.
DAS.REQ
DLA.REQ
MICE.REQ
None.
J. Diaz del Rio (ODC Space)
-Mice Version 1.0.0, 30-JUN-2021 (JDR)
end new segment in DLA file
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