dasadd_c |
Table of contents
Proceduredasadd_c ( DAS, add data, double precision ) void dasadd_c ( SpiceInt handle, SpiceInt n, ConstSpiceDouble data [] ) AbstractAdd an array of double precision numbers to a DAS file. Required_ReadingDAS KeywordsARRAY ASSIGNMENT DAS FILES Brief_I/OVARIABLE I/O DESCRIPTION -------- --- -------------------------------------------------- handle I DAS file handle. n I Number of d.p. numbers to add to DAS file. data I Array of d.p. numbers to add. Detailed_Inputhandle is a file handle of a DAS file opened for writing. n is the number of double precision "words" to add to the DAS file specified by `handle'. data is an array of double precision numbers to be added to the specified DAS file. Elements 0 through n-1 are appended to the double precision data in the file. Detailed_OutputNone. See -Particulars for a description of the effect of this routine. ParametersNone. Exceptions1) If the input file handle is invalid, an error is signaled by a routine in the call tree of this routine. 2) If an I/O error occurs during the data addition attempted by this routine, the error is signaled by a routine in the call tree of this routine. 3) If the input count `n' is less than 1, no data will be added to the specified DAS file. No error will be signaled. FilesSee the description of the argument `handle' in -Detailed_Input. ParticularsThis routine adds double precision data to a DAS file by "appending" them after any double precision data already in the file. The sense in which the data are "appended" is that the data will occupy a range of logical addresses for double precision data that immediately follow the last logical address of a double precision number that is occupied at the time this routine is called. The diagram below illustrates this addition: +-------------------------+ | (already in use) | D.p. logical address 1 +-------------------------+ . . . +-------------------------+ | (already in use) | last d.p. logical address +-------------------------+ in use before call to dasadd_c | data[0] | +-------------------------+ . . . +-------------------------+ | data[n-1] | +-------------------------+ The logical organization of the double precision numbers in the DAS file is independent of the location in the file of any data of integer or character type. The actual physical write operations that add the input array `data' to the indicated DAS file might not take place before this routine returns, since the DAS system buffers data that are written as well as data that are 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 update double precision logical addresses that already contain data, the CSPICE routine dasudd_c (DAS update data, double precision) should be used. ExamplesThe 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) Create a new DAS file and add 200 double precision numbers to it. Close the file, then re-open it and read the data back out. Example code begins here. /. Program dasadd_ex1 ./ #include <stdio.h> #include "SpiceUsr.h" int main( ) { /. Local parameters. ./ #define FNAME "dasadd_ex1.das" #define TYPE "TEST" /. Local variables. ./ SpiceDouble data [200]; 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 ); /. Fill the array `data' with the double precision numbers 1.0 through 100.0, and add this array to the file. ./ for ( i = 1; i <= 100; i++ ) { data[i-1] = (double)( i ); } dasadd_c ( handle, 100, data ); /. Now append the array `data' to the file again. ./ dasadd_c ( handle, 100, data ); /. Close the file. ./ dascls_c ( handle ); /. Now verify the addition of data by opening the file for read access and retrieving the data. ./ dasopr_c ( FNAME, &handle ); dasrdd_c ( handle, 1, 200, data ); /. Dump the data to the screen. We should see the sequence 1.0, 2.0, ..., 100.0, 1.0, 2.0, ... , 100.0. The numbers will be represented as double precision numbers in the output. ./ 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 "dasadd_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 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 Note that after run completion, a new DAS file exists in the output directory. RestrictionsNone. Literature_ReferencesNone. Author_and_InstitutionJ. Diaz del Rio (ODC Space) Version-CSPICE Version 1.0.0, 09-MAR-2021 (JDR) Index_Entriesadd double precision data to a DAS file |
Fri Dec 31 18:41:03 2021