Index of Functions: A B C D E F G H I J K L M N O P Q R S T U V W X
Index Page dasudd_c

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Procedure Abstract Required_Reading Keywords Brief_I/O Detailed_Input | Detailed_Output Parameters Exceptions Files Particulars Examples | Restrictions Literature_References Author_and_Institution Version Index_Entries

#### Procedure

       dasudd_c ( DAS, update data, double precision )

       void dasudd_c ( SpiceInt            handle,
                       SpiceInt            first,
                       SpiceInt            last,
                       ConstSpiceDouble    data   [] )

#### Abstract

       Update data in a specified range of double precision addresses
       in a DAS file.

#### Required_Reading

       DAS

#### Keywords

       ARRAY
       ASSIGNMENT
       DAS
       FILES

#### Brief_I/O

       VARIABLE  I/O  DESCRIPTION
       --------  ---  --------------------------------------------------
       handle     I   DAS file handle.
       first,
       last       I   Range of d.p. addresses to write to.
       data       I   An array of d.p. numbers.

#### Detailed_Input

       handle      is a file handle of a DAS file opened for writing.

       first,
       last        are the first and last of a range of DAS logical
                   addresses of double precision numbers to update. These
                   addresses satisfy the inequality

                      1  <=   first   <=   last   <=   lastd

                   where `lastd' is the last double precision logical
                   address in use in the DAS file designated by
                   `handle'.

       data        is an array of double precision numbers. The
                   array elements data[0] through data[n-1] will be
                   written to the indicated DAS file, where `n' is
                   last - first + 1.

#### Detailed_Output

       None.

       See -Particulars for a description of the effect of this routine.

#### Parameters

       None.

#### Exceptions

       1)  If the input file handle is invalid, an error is
           signaled by a routine in the call tree of this routine.

       2)  Only logical addresses that already contain data may be
           updated: if either `first' or `last' are outside the range

              [ 1,  lastd ]

           where `lastd' is the last double precision logical address that
           currently contains data in the indicated DAS file, the error
           SPICE(INVALIDADDRESS) is signaled by a routine in the call tree of
           this routine. The DAS file will not be modified.

       3)  If first > last but both addresses are valid, this routine
           will not modify the indicated DAS file. No error will be
           signaled.

       4)  If an I/O error occurs during the data update attempted
           by this routine, the error is signaled by a routine in the
           call tree of this routine.

#### Files

       See the description of the argument `handle' in -Detailed_Input.

#### Particulars

       This routine replaces the double precision data in the specified
       range of logical addresses within a DAS file with the contents of
       the input array `data'.

       The actual physical write operations that update the indicated
       DAS file with the contents of the input array `data' might not take
       place before this routine returns, since the DAS system buffers
       data that is written as well as data that is read. In any case,
       the data will be flushed to the file at the time the file is
       closed, if not earlier. A physical write of all buffered
       records can be forced by calling the CSPICE routine daswbr_c
       (DAS, write buffered records).

       In order to append double precision data to a DAS file, filling
       in a range of double precision logical addresses that starts
       immediately after the last double precision logical address
       currently in use, the CSPICE routine dasadd_c (DAS add data,
       double precision) should be used.

#### Examples

       The numerical results shown for this example may differ across
       platforms. The results depend on the SPICE kernels used as
       input, the compiler and supporting libraries, and the machine
       specific arithmetic implementation.

       1) Write to addresses 1 through 200 in a DAS file in random-access
          fashion by updating the file. Recall that data must be present
          in the file before it can be updated.

          Example code begins here.

          /.
             Program dasudd_ex1
          ./
          #include <stdio.h>
          #include "SpiceUsr.h"

          int main( )
          {

             /.
             Local parameters.
             ./
             #define FNAME        "dasudd_ex1.das"
             #define TYPE         "TEST"

             /.
             Local variables.
             ./
             SpiceDouble          data   [200];
             SpiceDouble          udata;

             SpiceInt             handle;
             SpiceInt             i;
             SpiceInt             j;

             /.
             Open a new DAS file. Use the file name as the internal
             file name, and reserve no records for comments.
             ./
             dasonw_c ( FNAME, TYPE, FNAME, 0, &handle );

             /.
             Append 200 double precision numbers to the file;
             after the data are present, we're free to update it
             in any order we please.  (cleard_c zeros out a double
             precision array.)
             ./
             cleard_c ( 200, data );
             dasadd_c ( handle, 200, data );

             /.
             Now the double precision logical addresses 1:200
             can be written to in random-access fashion.  We'll
             fill them in reverse order.
             ./
             for ( i = 200; i >= 1; i -= 1 )
             {
                udata = (double)i;
                dasudd_c ( handle, i, i, &udata );
             }

             /.
             Close the file.
             ./
             dascls_c ( handle );

             /.
             Now make sure that we updated the file properly.
             Open the file for reading and dump the contents
             of the double precision logical addresses 1:200.
             ./
             dasopr_c ( FNAME, &handle );

             cleard_c ( 200, data );
             dasrdd_c ( handle, 1, 200, data );

             printf( "\n" );
             printf( "Data from \"%s\":\n", FNAME );
             printf( "\n" );
             for ( i = 0; i < 25; i++ )
             {
                for ( j = 0; j < 8; j++ )
                {
                   printf( "%7.1f", data[i*8+j] );
                }
                printf( "\n" );
             }

             /.
             Close the file.
             ./
             dascls_c ( handle );

             return ( 0 );
          }

          When this program was executed on a Mac/Intel/cc/64-bit
          platform, the output was:

          Data from "dasudd_ex1.das":

              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   51.0   52.0   53.0   54.0   55.0   56.0
             57.0   58.0   59.0   60.0   61.0   62.0   63.0   64.0
             65.0   66.0   67.0   68.0   69.0   70.0   71.0   72.0
             73.0   74.0   75.0   76.0   77.0   78.0   79.0   80.0
             81.0   82.0   83.0   84.0   85.0   86.0   87.0   88.0
             89.0   90.0   91.0   92.0   93.0   94.0   95.0   96.0
             97.0   98.0   99.0  100.0  101.0  102.0  103.0  104.0
            105.0  106.0  107.0  108.0  109.0  110.0  111.0  112.0
            113.0  114.0  115.0  116.0  117.0  118.0  119.0  120.0
            121.0  122.0  123.0  124.0  125.0  126.0  127.0  128.0
            129.0  130.0  131.0  132.0  133.0  134.0  135.0  136.0
            137.0  138.0  139.0  140.0  141.0  142.0  143.0  144.0
            145.0  146.0  147.0  148.0  149.0  150.0  151.0  152.0
            153.0  154.0  155.0  156.0  157.0  158.0  159.0  160.0
            161.0  162.0  163.0  164.0  165.0  166.0  167.0  168.0
            169.0  170.0  171.0  172.0  173.0  174.0  175.0  176.0
            177.0  178.0  179.0  180.0  181.0  182.0  183.0  184.0
            185.0  186.0  187.0  188.0  189.0  190.0  191.0  192.0
            193.0  194.0  195.0  196.0  197.0  198.0  199.0  200.0

          Note that after run completion, a new DAS file exists in the
          output directory.

#### Restrictions

       None.

#### Literature_References

       None.

#### Author_and_Institution

       J. Diaz del Rio     (ODC Space)

#### Version

       -CSPICE Version 1.0.0, 16-JUL-2021 (JDR)

#### Index_Entries

       update double precision data in a DAS file

#### Link to routine dasudd_c source file dasudd_c.c

    Fri Dec 31 18:41:04 2021