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JSX Visualization Color, Label and further Stylings

After defining the variables, you can add label, color and transparencies for the variables.
Both only affect their appearance in the canvases.

Adding labels to variables

Labels are added with the command \label{varname}{labeltext} within the environment of
the visualization, but outside of the variable-environment, canvas-environment etc.

For labeltext, currently you can only use standard text, but it will be improved to allow
LaTeX-commands. Usually, the label will be displayed next to the object in the canvas(es).
An exception is the slider. Here the value shown next to the slider will be replaced by
labeltext=value.

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\begin{variables}
    \slider{s}{real}{1}{-4}{4}
  \point{p}{real}{0,0}
  \point{q}{real}{s,2}
  \line{g}{real}{p,q}
\end{variables}
 
%set up label
\label{p}{P} %sets the label 'P' to p
\label{q}{Q} %sets the label 'Q' to q
\label{s}{Q[x]} % next to the slider is shown 'Q[x]=...' instead of just the value.
 
\begin{canvas}
   \plotSize{250,250}
     \plotLeft{-5}
     \plotRight{5}
     \plotTop{5}
     \plot[coordinateSystem, noToolbar]{p,q,s,g}    
\end{canvas}

Changing the color of variables

The default color of an object is changed by the command \color{varname}{color}.
While defining colors you can also optionally
define the transparency between 0 and 1 where 0 has no transparency at all,
and 1 will make the plotted variable object not visible.

As color, you can use any HTML-color name (see e.g. https://www.w3schools.com/colors/colors_names.asp ), or any hex-code defining a color,
e.g. #32CD32 which would be the same as the color LimeGreen.

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\begin{variables}
    \slider{s}{real}{1}{-4}{4}
  \point{p}{real}{0,0}
  \point{q}{real}{s,2}
  \line{g}{real}{p,q}
\end{variables}
 
 
\color{p}{RED} %set color of p to red
\color[0.1]{g}{DARKGREEN} % set color of g to dark green with 10% transparency

Coloring the points of sequences

For sequences it is possible to color the single points differently depending on conditions.

For example the line \color{seq}{\IFELSE{seq[n] < 0}{red}{green}} would cause that those points of the sequence seq are colored red which lie below the x-axis, and the others green. The IFELSE-syntax is the same as in visualization text and is explained here.

Caution: In the IFELSE-condition, you are only allowed to use those variables which are defined before (!) the sequence variable is defined.

Further stylings

The default styling of variables in the canvas can be changed by the command \style{varname}{styling-options}. The styling-options here is a comma-separated list of options that JSXGraph offers for styling, e.g. for a point with varname p you can use \style{p}{face:'[]', size:10} to display the point as a big square.

See the JSXGraph documentation for more details on the options available.
Specifically for