Determining axis values at a mouse poisition

[javageek]

I am trying to come up with the code to take the location of a mouse pointer and determine the value of the domain and value axis that cooresponds to that location.

I set up a ChartMouseListener on the ChartPanel and can pick up the X and Y coordinates from the MouseEvent trigger in the chartMouseMoved method. But I can't figure out how to get from X,Y to the axis values. I also expect that the pointer can be between points. Which means I have to also pick the closest value to any specific point. I have searched and searched the API and can't find anything that obviously does either function for me. I sure could use a suggestion.

What I am trying to accomplish is to pick up the proper axis data values and display them at the crosshair lines.

[sarsipius]

This is what I do to get the domain/range coordinates:

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double x = plot.getDomainAxis().java2DToValue(cp.translateScreenToJava2D(evt.getTrigger().getPoint()).getX(),cp.getChartRenderingInfo().getPlotInfo().getDataArea(),plot.getDomainAxisEdge());

double y = plot.getRangeAxis().java2DToValue(cp.translateScreenToJava2D(evt.getTrigger().getPoint()).getY(),cp.getChartRenderingInfo().getPlotInfo().getDataArea(),plot.getRangeAxisEdge());

Hope this will help you

[javageek]

That helped a lot. I am now able to get the value of the x and y axis. Thank you very much!!!

One more question. Is it possible to also get the index of the domain axis instead of the actual value?

[sarsipius]

I'm not sure if this is what you want ::

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int rowIndex = dataset.getRowIndex(((CategoryItemEntity)evt.getEntity()).getRowKey());
int columnIndex = dataset.getColumnIndex(((CategoryItemEntity)evt.getEntity()).getColumnKey());