Changes to RegressionVisualization 3D view and volume plot

[jamesfishbaugh]

I would like to request some small changes to the 3D view and volume plot:

• When the sequence is created and first displayed, center and zoom in on the shape
• Plot the regression volume as a solid line
• Change the default location of the legend, top-middle or bottom-middle preferably so as not to obstruct data
• Optional: Have the legend be draggable to any location in the plot

[phcerdan]

Also, the plotting in RegressionVisualization requires a CSV input file, and does not seem to be using the input already provided.

Do we require this CSV file for plotting or can we reuse the already provided folder, or use the generated Sequence?
Options:
a) Work with the Sequence node that is generated in the Shape Regression Inputs
b) Or create a RegressionPlot module, with its own input requirements

What do you think?

[jamesfishbaugh]

@phcredan the sequence is only a series of vtk shapes. The CSV file contains the rest of the information needed to make the graph, namely the volume of the shape observations, and the time interval of the sequence. The interface for "Regression's Input Shapes" can be improved to make this much more clear.

For your ideas, I prefer to keep the sequence and volume plot together in the same modules, as the volume plot is very helpful for assessing model fit. What I have added in a recent update is to auto populate the CSV file, since the CSV file will have a known name and will be in the same directory as the one the user chose for the input directory. This way, a user can create the sequence, and then just click plot.

[phcerdan]

Sounds good @jamesfishbaugh, could you provide one of those folders with the csv + vtk shapes? I would like to test the plot to help with this issue.

[jamesfishbaugh]

@phcerdan sure, here is a folder with the input shapes, and an output folder with the sequence and the CSV file. You will have to edit the CSV to modify the paths for your system.

regression_example.zip

[phcerdan]

Thanks @jamesfishbaugh, I got this:

Does it look similar to what you get?

Plot the regression volume as a solid line

Aren't the two lines already too similar?

Change the default location of the legend, top-middle or bottom-middle preferably so as not to obstruct data

I agree, will have a look

[jamesfishbaugh]

@phcerdan There are a couple of issues with the plot, they are very simple:

• For some reason, the two series are using their indices for the x-axis, rather than the actual time point (1.1 to 6.1 in this case). I have verified the vtkTables are getting the right float values, so for the life of me I can't figure out why it is plotting integer indices.
• I would like 'Shape Input' series plotted with just dots (no line connecting). Again, this should be simple but my calls to SetPlotType do not have the desired effect.
• The 'Shape Regression' series should be plotted only as a line, there is no need to see the dots which only denote the sampling.

Could you look into this?

[phcerdan]

Yeah, I will put this in my todo list, will find time soon. Thanks for the details.

[jamesfishbaugh]

@phcerdan thanks. I was actually able to fix the styling, the only thing left is the proper x-axis values:

• For some reason, the two series are using their indices for the x-axis, rather than the actual time point (1.1 to 6.1 in this case). I have verified the vtkTables are getting the right float values, so for the life of me I can't figure out why it is plotting integer indices.
• I would like 'Shape Input' series plotted with just dots (no line connecting). Again, this should be simple but my calls to SetPlotType do not have the desired effect.
• The 'Shape Regression' series should be plotted only as a line, there is no need to see the dots which only denote the sampling.

[jamesfishbaugh]

@phcerdan I believe the issue with the plot stems from a bug in the chart. If I change the plot type to 'Scatter', the data is plotted correctly. Do you know where to report this issue?

[phcerdan]

Cool, opening an issue in https://discourse.slicer.org/c/dev might help, expose the problem and the differences between the two types. Maybe, who knows, is not a bug, but a feature :)