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B.2.1 Usage

The usage of calc is

   stilts <stilts-flags> calc table=<table>
                              [expression=]<expr>
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. For programmatic invocation, the Task class for this command is uk.ac.starlink.ttools.task.Calc.

Parameter values are assigned on the command line as explained in Section 2.3. They are as follows:

expression = <expr>       (String)
An expression to evaluate. The functions in Section 10.7 can be used.
table = <table>       (StarTable)
A table which provides the context within which expression is evaluated. This parameter is optional, and will usually not be required; its only purpose is to allow use of constant expressions (table parameters) associated with the table. These can be referenced using identifiers of the form param$*, ucd$* or utype$* - see Section 10.2 for more detail.


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STILTS - Starlink Tables Infrastructure Library Tool Set
Starlink User Note256
STILTS web page: http://www.starlink.ac.uk/stilts/
Author email: m.b.taylor@bristol.ac.uk
Mailing list: topcat-user@jiscmail.ac.uk