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8.3.12 function

Plots an analytic function. This layer is currently only available for the Plane plots (including histogram).

Usage Overview:

   layerN=function axisN=Horizontal|Vertical xnameN=<name> fexprN=<expr>
                   colorN=<rrggbb>|red|blue|... thickN=<pixels>
                   dashN=dot|dash|...|<a,b,...> antialiasN=true|false

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

antialiasN = true|false       (Boolean)
If true, plotted lines are drawn with antialising. Antialised lines look smoother, but may take perceptibly longer to draw. Only has any effect for bitmapped output formats.

[Default: false]

axisN = Horizontal|Vertical       (FuncAxis)
Which axis the independent variable varies along. Options are currently Horizontal and Vertical.

[Default: Horizontal]

colorN = <rrggbb>|red|blue|...       (Color)
The color of plotted data.

The value may be a six-digit hexadecimal number giving red, green and blue intensities, e.g. "ff00ff" for magenta. Alternatively it may be the name of one of the pre-defined colors. These are currently red, blue, green, grey, magenta, cyan, orange, pink, yellow, black, white.

[Default: ff0000]

dashN = dot|dash|...|<a,b,...>       (float[])
Determines the dash pattern of the line drawn. If null (the default), the line is solid.

Possible values for dashed lines are dot, dash, longdash, dotdash. You can alternatively supply a comma-separated list of on/off length values such as "4,2,8,2".

fexprN = <expr>       (String)
An expression using TOPCAT's expression language in terms of the independent variable to define the function. This expression must be standalone - it cannot reference any tables.
thickN = <pixels>       (Integer)
Thickness of plotted line in pixels.

[Default: 1]

xnameN = <name>       (String)
Name of the independent variable for use in the function expression. This is typically x for a horizontal independent variable and y for a vertical independent variable, but any string that is a legal expression language identifier (starts with a letter, continues with letters, numbers, underscores) can be used.

[Default: x]


Next Previous Up Contents
Next: skyvector
Up: Layer Types
Previous: histogram

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