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smalltalkpharoroassal

How to format chart in Roassal 3?

I made a chart following the examples in the documentation. I find the title and x/y labels too close to the plot itself, and the tick labels too small. How do I format them?

x := -3.14 to: 3.14 count: 100.
y := x sin.

c := RSChart new.
p := RSLinePlot new x: x y: y.
c addPlot: p.

c title: 'Sine function'.
c xlabel: 'X axis'.
c ylabel: 'Y axis'.

c addDecoration: RSHorizontalTick new.
c addDecoration: RSVerticalTick new.
c open

chart

Solution

  • The way the graph is constructed it uses the default offset of 5 for X axis and -5 for Y axis in the initialize of RSXLabelDecoration or RSYLabelDecoration respectively.

    To move the titles around you have to create them yourself instead of using xlabel or ylabel.

    You whould have to replace these two lines of code:

    c xlabel: 'X axis'.
c ylabel: 'Y axis'.

    with:

    xAxisDecoration := c addDecoration: (RSXLabelDecoration new title: 'X axis'; offset: 15).
yAxisDecoration := c addDecoration: (RSYLabelDecoration new title: 'Y axis'; offset: -15).

    The result:

    XY axis movement

    Edit - forgot about the tick labels

    To adjust the font size you need to add a message fontSize when creating a RSHorizontal(Vertical)Tick

    The affected code would look like this:

    c addDecoration: (RSHorizontalTick new fontSize: 10).
c addDecoration: (RSVerticalTick new fontSize: 10).

    Producing this result:

    enter image description here