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jfreechartforest-plots

Create forest plot using JFreeChart

Does anyone have an example of how to render a forest plot using JFreeChart (or another Java-based open source charting library, but JFreeChart is preferred due to the integration with Jasper Reports)?

See https://en.wikipedia.org/wiki/Forest_plot for description of the forest plot.

I was thinking about hacking somethign together using a horizontal bar chart where left side of the axis is the categorical value, and right side is the range, but the problem is the data for a forest plot comes in a set of data like: category, min, max. Such as an odd ratio with a confidence interval that spans between -.1 to 1.2. The forrest plot would basically be a line drawn between -.1 and 1.2 with a diamond marker directly in the middle (around .55).

If anyone has experience on building this visualization in JFreeChart, it would be much appreciated!

Solution

  • While this is not supported directly in the current release, a reasonable facsimile should be possible. Instead of a bar chart, consider using a MinMaxCategoryRenderer having PlotOrientation.HORIZONTAL and custom icons, as shown here. Add a CategoryMarker or CategoryLineAnnotation with a dashed Stroke to the CategoryPlot for the centerline; add a CategoryItemLabelGenerator to handle the labels.

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