Download CONVERT – A Format-conversion Package

SUN/55.31 —Specifications of CONVERT Applications
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NDF2ASCII
NDF2ASCII
Converts an NDF to a text file
Description:
This application converts an NDF to a Fortran text file. Only one of the array components
may be copied to the output file. Preceding the data there is an optional header consisting
of either the FITS extension with the values of certain keywords replaced by information
derived from the NDF, or a minimal FITS header also derived from the NDF. The output
file uses LIST carriagecontrol.
Usage:
ndf2ascii in out [comp] [reclen] noperec=?
Parameters:
COMP = LITERAL (Read)
The NDF component to be copied. It may be "Data", "Quality" or "Variance".
["Data"]
FITS = _LOGICAL (Read)
If TRUE, any FITS extension is written to start of the output file, unless there is no
extension whereupon a minimal FITS header is written to the ASCII file. [FALSE]
FIXED = _LOGICAL (Read)
When FIXED is TRUE, the output file allocates a fixed number of characters per data
value. The number of characters chosen is the minimum that prevents any loss of
precision, and hence is dependent on the data type of the NDF array. These widths in
characters for each HDS data type are as follows: _UBYTE, 3; _BYTE, 4; _UWORD, 5;
_WORD, 6; _INTEGER, 11; _INT64, 20; _REAL, 16; and _DOUBLE, 24. The record
length is the product of the number of characters per value plus one (for a delimiting
space), times the number of values per record given by parameter NOPEREC, up to a
maximum of 512.
When FIXED is FALSE, data values are packed as efficiently as possible within each
record. The length of each record is given by Parameter RECLEN. [FALSE]
IN = NDF (Read)
Input NDF data structure. The suggested default is the current NDF if one exists,
otherwise it is the current value.
NOPEREC = _INTEGER (Read)
The number of data values per record of the output file, when FIXED is TRUE. It
should be positive on UNIX platforms. The suggested default is the current value, or
8 when there is not one. The upper limit is given by 512 divided by the number of
characters per value plus 1 (see Parameter FIXED).
OUT = FILENAME (Write)
Name of the output formatted Fortran file. The file will normally have variable-length
records when there is a header, but always fixed-length records when there is no
header.