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6.1.31 stats

Usage:

   stats [<item> ...]

Calculates statistics on the data in the table. This filter turns the table sideways, so that each row of the output corresponds to a column of the input. The columns of the output table contain statistical items such as mean, standard deviation etc corresponding to each column of the input table.

By default the output table contains columns for the following items:

However, the output may be customised by supplying one or more <item> headings. These may be selected from the above as well as the following:

Additionally, the form "Q.nn" may be used to represent the quantile corresponding to the proportion 0.nn, e.g.:

Any parameters of the input table are propagated to the output one.

Note that quantile calculations (including median and quartiles) can be expensive on memory. If you want to calculate quantiles for large tables, it may be wise to reduce the number of columns to only those you need the quantiles for earlier in the pipeline. No interpolation is performed when calculating quantiles.


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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