| ekacld |
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Table of contents
Procedure
EKACLD ( EK, add d.p. column to segment )
SUBROUTINE EKACLD ( HANDLE, SEGNO, COLUMN, DVALS,
. ENTSZS, NLFLGS, RCPTRS, WKINDX )
Abstract
Add an entire double precision column to an EK segment.
Required_Reading
EK
Keywords
EK
Declarations
IMPLICIT NONE
INCLUDE 'ekcoldsc.inc'
INCLUDE 'eksegdsc.inc'
INCLUDE 'ektype.inc'
INTEGER HANDLE
INTEGER SEGNO
CHARACTER*(*) COLUMN
DOUBLE PRECISION DVALS ( * )
INTEGER ENTSZS ( * )
LOGICAL NLFLGS ( * )
INTEGER RCPTRS ( * )
INTEGER WKINDX ( * )
Brief_I/O
VARIABLE I/O DESCRIPTION
-------- --- --------------------------------------------------
HANDLE I EK file handle.
SEGNO I Number of segment to add column to.
COLUMN I Column name.
DVALS I Double precision values to add to column.
ENTSZS I Array of sizes of column entries.
NLFLGS I Array of null flags for column entries.
RCPTRS I Record pointers for segment.
WKINDX I-O Work space for column index.
Detailed_Input
HANDLE is the handle of an EK file that is open for writing.
A "begin segment for fast write" operation must
have already been performed for the designated
segment.
SEGNO is the number of the segment to which
data is to be added.
COLUMN is the name of the column to be added. All of
the data for the named column will be added in
one shot.
DVALS is an array containing the entire set of column
entries for the specified column. The entries
are listed in row-order: the column entry for the
first row of the segment is first, followed by the
column entry for the second row, and so on. The
number of column entries must match the declared
number of rows in the segment. For columns having
fixed-size entries, a null entry must be allocated
the same amount of space occupied by a non-null
entry in the array DVALS. For columns having
variable-size entries, null entries do not require
any space in the DVALS array, but in any case must
have their allocated space described correctly by
the corresponding element of the ENTSZS array
(described below).
ENTSZS is an array containing sizes of column entries.
The Ith element of ENTSZS gives the size of the
Ith column entry. ENTSZS is used only for columns
having variable-size entries. For such columns,
the dimension of ENTSZS must be at least NROWS.
The size of null entries should be set to zero.
For columns having fixed-size entries, the
dimension of this array may be any positive value.
NLFLGS is an array of logical flags indicating whether
the corresponding entries are null. If the Ith
element of NLFLGS is .FALSE., the Ith column entry
defined by DVALS and ENTSZS is added to the
current segment in the specified kernel file.
If the Ith element of NLFGLS is .TRUE., the
contents of the Ith column entry are undefined.
NLFLGS is used only for columns that allow null
values; it's ignored for other columns.
RCPTRS is an array of record pointers for the input
segment. This array is obtained as an output
from EKIFLD, the routine called to initiate a
fast write.
WKINDX is a work space array used for building a column
index. If the column is indexed, the dimension of
WKINDX must be at NROWS, where NROWS is the number
of rows in the column. If the column is not
indexed, this work space is not used, so the
dimension may be any positive value.
Detailed_Output
None. See $Particulars for a description of the effect of this
routine.
Parameters
None.
Exceptions
1) If HANDLE is invalid, an error is signaled by a routine in the
call tree of this routine.
2) If COLUMN is not the name of a declared column, an error is
signaled by a routine in the call tree of this routine.
3) If COLUMN specifies a column of whose data type is not
integer, the error SPICE(WRONGDATATYPE) is signaled.
4) If the specified column already contains ANY entries, an error
is signaled by a routine in the call tree of this routine.
5) If an I/O error occurs while reading or writing the indicated
file, the error is signaled by a routine in the call tree of
this routine.
Files
See the EK Required Reading ek.req for a discussion of the EK file
format.
Particulars
This routine operates by side effects: it modifies the named
EK file by adding data to the specified column. This routine
writes the entire contents of the specified column in one shot.
This routine creates columns much more efficiently than can be
done by sequential calls to EKACED, but has the drawback that
the caller must use more memory for the routine's inputs. This
routine cannot be used to add data to a partially completed
column.
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) Suppose we want to create an Sequence Component E-kernel
named 'ekacld_ex1.bes' which contains records of orders for
data products. The E-kernel has a table called DATAORDERS that
consists of the set of columns listed below:
DATAORDERS
Column Name Data Type
----------- ---------
ORDER_ID INTEGER
CUSTOMER_ID INTEGER
LAST_NAME CHARACTER*(*)
FIRST_NAME CHARACTER*(*)
ORDER_DATE TIME
COST DOUBLE PRECISION
The order database also has a table of items that have been
ordered. The columns of this table are shown below:
DATAITEMS
Column Name Data Type
----------- ---------
ITEM_ID INTEGER
ORDER_ID INTEGER
ITEM_NAME CHARACTER*(*)
DESCRIPTION CHARACTER*(*)
PRICE DOUBLE PRECISION
The file "ekacld_ex1.bdb" will contain two segments, the first
containing the DATAORDERS table and the second containing the
DATAITEMS table.
This example demonstrates how to open a new EK file and create
the first of the segments described above.
Use the LSK kernel below to load the leap seconds and time
constants required for the conversions.
naif0012.tls
Example code begins here.
PROGRAM EKACLD_EX1
IMPLICIT NONE
C
C Include the EK Column Name Size (CNAMSZ)
C
INCLUDE 'ekcnamsz.inc'
C
C Local parameters
C
CHARACTER*(*) LSK
PARAMETER ( LSK = 'naif0012.tls' )
CHARACTER*(*) TABLE
PARAMETER ( TABLE = 'DATAORDERS' )
INTEGER DECLEN
PARAMETER ( DECLEN = 200 )
INTEGER FNMLEN
PARAMETER ( FNMLEN = 50 )
INTEGER LNMLEN
PARAMETER ( LNMLEN = 50 )
INTEGER NAMLEN
PARAMETER ( NAMLEN = 40 )
INTEGER NCOLS
PARAMETER ( NCOLS = 6 )
INTEGER NROWS
PARAMETER ( NROWS = 9 )
INTEGER UTCLEN
PARAMETER ( UTCLEN = 30 )
C
C Local variables
C
CHARACTER*(DECLEN) CDECLS ( NCOLS )
CHARACTER*(CNAMSZ) CNAMES ( NCOLS )
CHARACTER*(FNMLEN) FNAMES ( NROWS )
CHARACTER*(LNMLEN) LNAMES ( NROWS )
CHARACTER*(NAMLEN) IFNAME
CHARACTER*(UTCLEN) ODATE
DOUBLE PRECISION COSTS ( NROWS )
DOUBLE PRECISION ETS ( NROWS )
INTEGER CSTIDS ( NROWS )
INTEGER HANDLE
INTEGER I
INTEGER NRESVC
INTEGER ORDIDS ( NROWS )
INTEGER RCPTRS ( NROWS )
INTEGER SEGNO
INTEGER SIZES ( NROWS )
INTEGER WKINDX ( NROWS )
LOGICAL NLFLGS ( NROWS )
C
C Load a leapseconds kernel for UTC/ET conversion.
C
CALL FURNSH ( 'naif0012.tls' )
C
C Open a new EK file. For simplicity, we will not
C reserve any space for the comment area, so the
C number of reserved comment characters is zero.
C The variable IFNAME is the internal file name.
C
NRESVC = 0
IFNAME = 'Test EK/Created 20-SEP-1995'
CALL EKOPN ( 'ekacld_ex1.bes', IFNAME, NRESVC, HANDLE )
C
C Set up the table and column names and declarations
C for the DATAORDERS segment. We'll index all of
C the columns. All columns are scalar, so we omit
C the size declaration. Only the COST column may take
C null values.
C
CNAMES(1) = 'ORDER_ID'
CDECLS(1) = 'DATATYPE = INTEGER, INDEXED = TRUE'
CNAMES(2) = 'CUSTOMER_ID'
CDECLS(2) = 'DATATYPE = INTEGER, INDEXED = TRUE'
CNAMES(3) = 'LAST_NAME'
CDECLS(3) = 'DATATYPE = CHARACTER*(*),' //
. 'INDEXED = TRUE'
CNAMES(4) = 'FIRST_NAME'
CDECLS(4) = 'DATATYPE = CHARACTER*(*),' //
. 'INDEXED = TRUE'
CNAMES(5) = 'ORDER_DATE'
CDECLS(5) = 'DATATYPE = TIME, INDEXED = TRUE'
CNAMES(6) = 'COST'
CDECLS(6) = 'DATATYPE = DOUBLE PRECISION,' //
. 'INDEXED = TRUE,' //
. 'NULLS_OK = TRUE'
C
C Start the segment. We presume the number of rows
C of data is known in advance.
C
CALL EKIFLD ( HANDLE, TABLE, NCOLS, NROWS,
. CNAMES, CDECLS, SEGNO, RCPTRS )
C
C At this point, arrays containing data for the
C segment's columns may be filled in. The names
C of the data arrays are shown below.
C
C Column Data array
C
C 'ORDER_ID' ORDIDS
C 'CUSTOMER_ID' CSTIDS
C 'LAST_NAME' LNAMES
C 'FIRST_NAME' FNAMES
C 'ORDER_DATE' ETS
C 'COST' COSTS
C
DO I = 1, NROWS
ORDIDS(I) = I
CSTIDS(I) = I * 100
COSTS(I) = I * 100.D0
CALL REPMI ( 'Order # Customer first name',
. '#', I, FNAMES(I) )
CALL REPMI ( 'Order # Customer last name',
. '#', I, LNAMES(I) )
CALL REPMI ( '1998 Mar #', '#', I, ODATE )
CALL UTC2ET ( ODATE, ETS(I) )
NLFLGS(I) = .FALSE.
END DO
NLFLGS(2) = .TRUE.
C
C The SIZES array shown below is ignored for scalar
C and fixed-size array columns, so we need not
C initialize it. For variable-size arrays, the
C Ith element of the SIZES array must contain the size
C of the Ith column entry in the column being written.
C Normally, the SIZES array would be reset for each
C variable-size column.
C
C The NLFLGS array indicates which entries are null.
C It is ignored for columns that don't allow null
C values. In this case, only the COST column allows
C nulls.
C
C Add the columns of data to the segment. All of the
C data for each column is written in one shot.
C
CALL EKACLI ( HANDLE, SEGNO, 'ORDER_ID',
. ORDIDS, SIZES, NLFLGS, RCPTRS, WKINDX )
CALL EKACLI ( HANDLE, SEGNO, 'CUSTOMER_ID',
. CSTIDS, SIZES, NLFLGS, RCPTRS, WKINDX )
CALL EKACLC ( HANDLE, SEGNO, 'LAST_NAME',
. LNAMES, SIZES, NLFLGS, RCPTRS, WKINDX )
CALL EKACLC ( HANDLE, SEGNO, 'FIRST_NAME',
. FNAMES, SIZES, NLFLGS, RCPTRS, WKINDX )
CALL EKACLD ( HANDLE, SEGNO, 'ORDER_DATE',
. ETS, SIZES, NLFLGS, RCPTRS, WKINDX )
CALL EKACLD ( HANDLE, SEGNO, 'COST',
. COSTS, SIZES, NLFLGS, RCPTRS, WKINDX )
C
C Complete the segment. The RCPTRS array is that
C returned by EKIFLD.
C
CALL EKFFLD ( HANDLE, SEGNO, RCPTRS )
C
C At this point, the second segment could be
C created by an analogous process. In fact, the
C second segment could be created at any time; it is
C not necessary to populate the first segment with
C data before starting the second segment.
C
C The file must be closed by a call to EKCLS.
C
CALL EKCLS ( HANDLE )
END
When this program is executed, no output is presented on
screen. After run completion, a new EK file exists in the
output directory.
Restrictions
1) Only one segment can be created at a time using the fast
write routines.
2) No other EK operation may interrupt a fast write. For
example, it is not valid to issue a query while a fast write
is in progress.
Literature_References
None.
Author_and_Institution
N.J. Bachman (JPL)
J. Diaz del Rio (ODC Space)
B.V. Semenov (JPL)
Version
SPICELIB Version 1.1.0, 12-AUG-2021 (JDR) (BVS)
Added IMPLICIT NONE statement.
Edited the header to comply with NAIF standard. and
created complete code example from existing fragment.
SPICELIB Version 1.0.1, 09-JAN-2002 (NJB)
Documentation change: instances of the phrase "fast load"
were replaced with "fast write."
Beta Version 1.0.0, 08-NOV-1995 (NJB)
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Fri Dec 31 18:36:17 2021