Using STILTS in Task Runner

Simple matching

STILTS is used via the AG Desktop Task Runner to crossmatch pairs of files in VOSpace. We describe here the simplest way to perform a match based on celestial position, on files in a standard format, VOTables.

• Use VOExplorer to find tskymatch2
• Click on Execute Task
• This gives you the Task Runner interface where you select the tables to be matched and the output destination.
• 'The entries illustrated are sufficient for 'well-formed' VOTables and other standard data but you can specify the column names etc. if necessary.
• Send the output to VOSpace unless it is very small as large tables will overflow the cache memory.

Complex matching

The full interface to STILTS allows table entires to be manipulated before or after crossmatching, and other operations; see the help for each input option in the Information panel in Task Runner and read the STILTS documentation.

• Use VOExplorer to find STILTS (it is one of the Remote applications under Examples) and click on Execute Task. This will launch the Task Runner for STILTS. Select Interface: tmatch2 from the drop-down menu to the right of the title bar in Task Runner.

• Using the panel on the left, select the files to be matched, in1 and in2, by clicking on the icon and then on Browse to make a File Explorer pop up.

• Select the output format ofmt. If you are using matcher sky then you must enter the names of the Right Ascension and Declination columns as values1 and values2 for each input table and enable params so that you can enter a search radius in arcsec. Finally, use the middle panel to enter the Output file destination and click on Execute at top right.

• This will produce a table containing the closest match (within 30 arcsec); only sources with matches are written out. The right-hand panel will tell you when the match has finished and you can download the table or send it to any suitable application such as TopCat.