Scatter plot radius doesn't seem to work?

General
1

I have a simple charting project where I am using a scatter plot in a DesktopChart to graph data points. I see in the ChartScatterDatapoint has a “Radius” property, which I the documentation suggests should specify the radius of the plotted circle representing the datapoint. But setting this property does not seem to have any effect. Is anyone else seeing this? Is this a bug?

Also, is there a method in a scatter plot to connect the points with lines? Is there a way to change the shape of the data point (that is, make it a cross or box or something else)?

2

Hi @Thomas_Moore

Make sure you set the Chart mode to Bubble instead of Scatter. When the chart is set to Scatter the radius value has no effect.

Also, is there a method in a scatter plot to connect the points with lines? Is there a way to change the shape of the data point (that is, make it a cross or box or something else)?

Yep, all that will arrive in a further release of Xojo: https://tracker.xojo.com/xojoinc/xojo/-/issues/72740

Screenshot_2023-05-16_at_15.29.06
Screenshot_2023-05-16_at_15.29.061884×1552 234 KB

3

I have noticed the same bug and was going to report it. Thank you!

4

Thanks, Xavier, for the explanation. It looks like from the link you sent that one will soon be able to put different shapes at data points and draw lines between them. The latter in particular is exactly what I need, so I look forward eagerly to the update.

Should the inability to use the radius property in the scatter plot be considered a bug in Xojo or in the documentation? Or should we wait to file a bug report until the release that corrects the bug you referenced and see whether it is fixed as a part of that?

5

Conceptually, documentation. Bubble and Scatter shares ChartScatterDatapoint that includes a radius ignored in scatter mode. Docs need some enhancements and clarifications.

About the concept: Scatter Plots | A Complete Guide to Scatter Plots

6

Probably a Documentation thing, because it is how it always worked in the original WebChart. I mean, when chart is set to scatter, then radius has no effect; when chart is set to Bubble then radius is taken into the play. In fact, the only difference between Scatter and Bubble modes is that one.