How to Refresh SharpPlot with new Data ?

[PGilbert]

If I do the following:

      ⎕USING∪←',sharpplot.dll' ',system.drawing.dll'
      sp1←⎕NEW Causeway.SharpPlot
      sp1.DrawLineGraph(,⊂⍳10)(⍳10)
      vw1←⎕NEW Causeway.SharpPlotViewer sp1
      vw1.Show ⍬

I get a plot as expected. Now I would like to 'Refresh' this plot with some new data like:

      sp1.DrawLineGraph(,⊂⍳20)(⍳20)  ⍝ I want to redraw the plot with that new X and Y
      vw1.Refresh  ⍝ Does not work
      vw1.Update  ⍝ Does not work

But the plot stays the same. What is the method to change the X and Y values of a plot in an existing opened window ?

Thanks in advance.

[Nicolas|Dyalog]

SharpPlot is a state machine. So if you call DrawLineGraph for a second time, it will draw a second chart on top of the first.
The philosophy behind this is the ability to create arbitrarily complex charts. The behaviour that you were expecting would mean that SharpPlot can only draw a single chart.

If you ever want to "undo" something, you have to start it all over again.

Similarly, to update the viewer, you need to reassign the SharpPlot instance

      ⎕USING∪←',sharpplot.dll' ',system.drawing.dll'
      sp1←⎕NEW Causeway.SharpPlot
      sp1.DrawLineGraph(,⊂⍳10)(⍳10)
      vw1←⎕NEW Causeway.SharpPlotViewer sp1
      vw1.Show ⍬

      sp1.DrawLineGraph(,⊂0.5×⍳10)(⍳10)  ⍝ draw a second line graph
      vw1.SharpPlot←sp1  ⍝ update viewer

      sp2←⎕NEW Causeway.SharpPlot    ⍝ create a new SharpPlot instance
      sp2.DrawLineGraph(,⊂0.5×⍳10)(⍳10)
      vw1.SharpPlot←sp2

[PGilbert]

Merci Nicolas, cela réponds bien à ma question.