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The usage of multicone
is
stilts <stilts-flags> multicone ifmt=<in-format> istream=true|false
icmd=<cmds> serviceurl=<value> ra=<expr>
dec=<expr> sr=<expr> verb=1|2|3
copycols=<colid-list> zerometa=true|false
ocmd=<cmds> omode=<out-mode> <mode-args>
out=<out-table> ofmt=<out-format>
[in=]<table>
If you don't have the stilts
script installed,
write "java -jar stilts.jar
" instead of
"stilts
" - see Section 3.
The available <stilts-flags>
are listed
in Section 2.1.
Parameter values are assigned on the command line
as explained in Section 2.3.
They are as follows:
-
copycols = <colid-list>
- List of columns from the input table which are to be copied
to the output table.
Each column identified here will be prepended to the
columns of the combined output table,
and its value for each row taken from the input table row
which provided the parameters of the query which produced it.
See Section 5.3 for list syntax.
-
dec = <expr>
- Expression which evaluates to the declination in degrees
in the J2000 coordinate system
for the request at each row of the input table.
This will usually be the name or ID of a column in the
input table, or a function involving one.
-
icmd = <cmds>
- Commands to operate on the input table,
before any other processing takes place.
The value of this parameter is one or more of the filter commands
described in Section 5.1.
If more than one is given, they must be separated by
semicolon characters (";").
This parameter can be repeated multiple times on the same
command line to build up a list of processing steps.
The sequence of commands given in this way
defines the processing pipeline which is performed on the table.
-
ifmt = <in-format>
- Specifies the format of the input table
(one of the known formats listed in Section 4.1).
This flag can be used if you know what format your input
table is in.
If it has the special value
(auto)
(the default),
then an attempt will be
made to detect the format of the table automatically.
This cannot always be done correctly however, in which case
the program will exit with an error explaining which
formats were attempted.
[Default: (auto)
]
-
in = <table>
- The location of the input table.
This is usually a filename or URL, and may point to a file
compressed in one of the supported compression formats
(Unix compress, gzip or bzip2).
If it is omitted, or equal to the special value "-",
the input table will be read from standard input.
In this case the input format must be given explicitly
using the
ifmt
parameter.
-
istream = true|false
- If set true, the
in
table
will be read as a stream.
It is necessary to give the
ifmt
parameter
in this case.
Depending on the required operations and processing mode,
this may cause the read to fail (sometimes it is necessary
to read the input table more than once).
It is not normally necessary to set this flag;
in most cases the data will be streamed automatically
if that is the best thing to do.
However it can sometimes result in less resource usage when
processing large files in certain formats (such as VOTable).
[Default: false
]
-
ocmd = <cmds>
- Commands to operate on the output table,
after all other processing has taken place.
The value of this parameter is one or more of the filter commands
described in Section 5.1.
If more than one is given, they must be separated by
semicolon characters (";").
This parameter can be repeated multiple times on the same
command line to build up a list of processing steps.
The sequence of commands given in this way
defines the processing pipeline which is performed on the table.
-
ofmt = <out-format>
- Specifies the format in which the output table will be written
(one of the ones in Section 4.2 - matching is
case-insensitive and you can use just the first few letters).
If it has the special value
"
(auto)
"
(the default),
then the output filename will be
examined to try to guess what sort of file is required
usually by looking at the extension.
If it's not obvious from the filename what output format is
intended, an error will result.
This parameter must only be given if
omode
has its default value of "out
".
[Default: (auto)
]
-
omode = <out-mode> <mode-args>
- The mode in which the result table will be output.
The default mode is
out
, which means that
the result will be written as a new table to disk or elsewhere,
as determined by the out
and ofmt
parameters.
However, there are other possibilities, which correspond
to uses to which a table can be put other than outputting it,
such as displaying metadata, calculating statistics,
or populating a table in an SQL database.
For some values of this parameter, additional parameters
(<mode-args>
)
are required to determine the exact behaviour.
Possible values are out
, meta
, stats
, count
, cgi
, discard
, topcat
, plastic
and tosql
.
Use the help=omode
flag
or see Section 5.4 for more information.
[Default: out
]
-
out = <out-table>
- The location of the output table. This is usually a filename
to write to.
If it is equal to the special value "-" (the default)
the output table will be written to standard output.
This parameter must only be given if
omode
has its default value of "out
".
[Default: -
]
-
ra = <expr>
- Expression which evaluates to the right ascension in degrees
in the J2000 coordinate system
for the request at each row of the input table.
This will usually be the name or ID of a column in the
input table, or a function involving one.
-
serviceurl = <value>
- The base part of a URL which defines the queries to be made.
Additional parameters will be appended to this using CGI syntax
("
name=value
", separated by '&' characters).
If this value does not end in either a '?' or a '&',
one will be added as appropriate.
Note that the regquery
command can be used to locate the service URL for cone search
services.
-
sr = <expr>
- Expression which evaluates to the search radius in degrees
for the request at each row of the input table.
This will often be a constant numerical value, but may be
the name or ID of a column in the input table,
or a function involving one.
-
verb = 1|2|3
- Verbosity level of the tables returned by the query service.
A value of 1 indicates the bare minimum and
3 indicates all available information.
-
zerometa = true|false
- Determines where the metadata for the output table comes from.
If true, an initial query is made to the service
with search radius set to zero. Cone search services are
supposed to respond to such requests with a metadata-only
table giving column information etc but no data.
Unfortunately, many services in practice respond with metadata
which is incommpatible with successful data queries,
which means the other queries cannot be used by
multicone
.
The default setting of false instead picks up the metadata
from the first non-empty data request. This is less likely
to fail, but doesn't stream data so well on output.
[Default: false
]
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Next: Examples
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STILTS - Starlink Tables Infrastructure Library Tool Set
Starlink User Note
256
STILTS web page:
http://www.starlink.ac.uk/stilts/
Author email:
m.b.taylor@bristol.ac.uk