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A Library for Handling
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Description:
This
routine copies all data values from a named column into a supplied buffer
Invocation
CALL
AST_GETCOLUMNDATA( THIS, COLUMN, RNULL, DNULL, MXSIZE, COLDATA, NELEM, STATUS )
Arguments
THIS = INTEGER (Given)
COLUMN = CHARACTER
(
)
(Given)
The character string holding the name of the column. Trailing spaces are ignored.
RNULL =
REAL (Given)
The value to return in COLDATA for any cells for which no value has been stored in
the FitsTable. Ignored if the column’ s data type is not AST__FLOATTYPE. Supplying AST__NANR
will cause a single precision IEEE NaN value to be used.
DNULL = REAL (Given)
The value to
return in COLDATA for any cells for which no value has been stored in the FitsTable. Ignored if the
column’ s data type is not AST__DOUBLETYPE. Supplying AST__NAN will cause a double precision
IEEE NaN value to be used.
MXSIZE = INTEGER (Given)
The size of the COLDATA array, in bytes.
The amount of memory needed to hold the data from a column may be determined using
AST_COLUMNSIZE. If the supplied array is too small to hold all the column data, trailing column
values will be omitted from the returned array, but no error will be reported.
COLDATA(
) =
BYTE (Given)
An area of memory in which to return the data values currently stored in the column.
The values are stored in row order. If the column holds non-scalar values, the elements of each value
are stored in " Fortran" order. No data type conversion is performed - the data type of each returned
value is the data type associated with the column when the column was added to the table. If the
column holds strings, the returned strings will be null terminated. Any excess room at the end of the
array will be left unchanged.
NELEM = INTEGER (Return)
The number of elements returned in the
COLDATA array. This is the product of the number of rows returned and the number of elements in
each column value.
STATUS = INTEGER (Given and Returned)
The global status.
Notes:
-
The RNULL and DNULL arguments specify the value to be returned for any empty cells
within columns holding floating point values. For columns holding integer values, the value
returned for empty cells is the value returned by the AST_COLUMNNULL functiom. For
columns holding string values, the ASCII NULL character is returned for empty cells.
Copyright (C) 2021 East Asian Observatory
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A Library for Handling
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Systems
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