The location of a serialized input table,
usually given using the
in parameter or similar,
may be given in one of the forms listed below.
file:///path/to/file. This is similar to specifying the filename directly, but there is a difference: using this form forces reads to be sequential rather than random access, which may allow you to experience a different set of performance characteristics and bugs.
myspace:/survey/iras_psc.xml", and can access files in the myspace are that the user is currently logged into. These URLs can be used for both input and output of tables. To use them you must have an AstroGrid account and the AstroGrid WorkBench or similar must be running; if you're not currently logged in a dialogue will pop up to ask you for name and password.
ivo://uk.ac.le.star/filemanager#node-2583". These URLs can be used for both input and output of tables. To use them you must have an AstroGrid account and the AstroGrid WorkBench or similar must be running; if you're not currently logged in a dialogue will pop up to ask you for name and password.
<syscmd" or "syscmd
<" character or ends with a "
|" character, the rest of the string is taken as a command line to be executed by the system shell. For instance a location like "
<cat header.txt data.txt" (or equivalently "
cat header.txt data.txt|") could be used to prepend a header line to an ASCII data file before it is passed to the STILTS ASCII-format input handler. Note this syntax will probably only work on Unix-like systems.
In any of these cases, for input locations compression is taken care
of automatically. That means that you can give the filename or URL
of a file which is compressed using
compress and the program will uncompress it on the fly.
For file formats that can contain multiple tables,
the one required, if it's not the first in the file,
can generally be specified by a position indicator string
appended to the basic location following a "
For instance "cat.fits#3" references HDU 3 in a multi-extension FITS file.
The details of this syntax depend on the file format,
and are given in the relevant subsection of
Note that tables can also be supplied from non-serialized sources, as described in Input Schemes.