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8.4.6 aux

Paints markers in a colour determined by the value of an additional data coordinate. The marker colours then represent an additional dimension of the plot. You can also adjust the transparency of the colours used. The way that data values are mapped to colours is usually controlled by options at the level of the plot itself, rather than by per-layer configuration.

Usage:

   shadingN=aux auxN=<num-expr> opaqueN=<number>

All the parameters listed here affect only the relevant layer, identified by the suffix N.

Associated parameters are as follows:

auxN = <num-expr>       (String)
Colour coordinate for Aux shading.

This parameter gives a column name, fixed value, or algebraic expression for the aux coordinate for layer N. The value is a numeric algebraic expression based on column names as described in Section 10.

opaqueN = <number>       (Double)
The opacity of points plotted in the Aux colour. The value is the number of points which have to be overplotted before the background is fully obscured.

[Default: 1.0]


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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@bristol.ac.uk