Table of contents
CSPICE_DASADD adds an array of double precision numbers to a DAS file.
Given:
handle a file handle of a DAS file opened for writing.
help, handle
LONG = Scalar
data an array of double precision numbers to be added to the
specified DAS file.
help, data
DOUBLE = Array[N]
Elements 0 through N-1 are appended to the double precision
data in the file.
the call:
cspice_dasadd, handle, data
returns:
None.
See -Particulars for a description of the effect of 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 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.
PRO dasadd_ex1
;;
;; Local parameters.
;;
FNAME = 'dasadd_ex1.das'
TYPE = 'TEST'
;;
;; Local variables.
;;
data = dblarr(100)
;;
;; Open a new DAS file. Use the file name as the internal
;; file name, and reserve no records for comments.
;;
cspice_dasonw, FNAME, TYPE, FNAME, 0L, handle
;;
;; Fill the array `data' with the double precision
;; numbers 1.0 through 100.0, and add this array
;; to the file.
;;
for i=1L, 100L do begin
data[i-1] = DOUBLE( i )
endfor
cspice_dasadd, handle, data
;;
;; Now append the array `data' to the file again.
;;
cspice_dasadd, handle, data
;;
;; Close the file.
;;
cspice_dascls, handle
;;
;; Now verify the addition of data by opening the
;; file for read access and retrieving the data.
;;
cspice_dasopr, FNAME, handle
cspice_dasrdd, handle, 1L, 200L, 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.
;;
print
print, 'Data from "', FNAME, '":'
print
for i=0L, 24L do begin
print, format='(8F7.1)', data[i*8:i*8+7]
endfor
;;
;; Close the file.
;;
cspice_dascls, handle
END
When this program was executed on a Mac/Intel/IDL8.x/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.
This 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 cspice_dasadd
| 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 Icy routine cspice_daswbr (DAS, write
buffered records).
In order to update double precision logical addresses that
already contain data, the Icy routine cspice_dasudd
(DAS update data, double precision) should be used.
1) 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 any of the input arguments, `handle' or `data', is
undefined, an error is signaled by the IDL error handling
system.
4) If any of the input arguments, `handle' or `data', is not of
the expected type, or it does not have the expected dimensions
and size, an error is signaled by the Icy interface.
See the description of the argument `handle' in -I/O.
None.
DAS.REQ
ICY.REQ
None.
J. Diaz del Rio (ODC Space)
-Icy Version 1.0.0, 09-JUN-2021 (JDR)
add double precision data to a DAS file
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