Investigate Options for Multiple Rebinning

[Owen Arnold]

From problem reported by Jon Taylor: Cannot visualise an visually rebin more than one MDWorkspace in the VSI at any one time.

Report options available going forward. No code required.

[Owen Arnold]

This is how to create a couple of similar(ish) MD Workspaces that can be used for comparison in the VSI

WS_A=CreateMDWorkspace(Dimensions='3',Extents='-10,10,-10,10,-10,10',Names='H,K,L',Units='A,A,A')
FakeMDEventData(InputWorkspace=WS_A,PeakParams='1000,0,0,0,1',RandomizeSignal='1')
A = SliceMD(InputWorkspace=WS_A,AlignedDim0='H,-10,10,10',AlignedDim1='K,-10,10,10',AlignedDim2='L,-10,10,10',OutputExtents='0,10,0,10,0,10',OutputBins='5,5,5',TakeMaxRecursionDepthFromInput='0',MaxRecursionDepth='10')

WS_B=CreateMDWorkspace(Dimensions='3',Extents='-10,10,-10,10,-10,10',Names='H,K,L',Units='A,A,A')
FakeMDEventData(InputWorkspace=WS_B,UniformParams='10000')
B = SliceMD(InputWorkspace=WS_B,AlignedDim0='H,-10,10,10',AlignedDim1='K,-10,10,10',AlignedDim2='L,-10,10,10',OutputExtents='0,10,0,10,0,10',OutputBins='5,5,5',TakeMaxRecursionDepthFromInput='0',MaxRecursionDepth='10')

[Owen Arnold]

These are my Report options:

1) Do the rebinning outside of the VSI (SliceMD/BinMD), then load the workspaces into the VSI. That way you will not hit the single-rebinner restriction.

2) Save the workspaces and open them in Paraview, then branch the pipeline and use the Rebinning operator to rebin each branch. The views can then be split (view each branch in a different sub-window) and locked together for comparison.

-- The following options would require code changes

3) Allow multiple Rebinning operator instances in the VSI, but it's not really geared up for this, and Michael has deliberately disabled this operation (and some other similar ones) where confusion with the views could occur. Also there's no good facilities for viewing the data side by side.

4) Keep the current workflow as it is, but allow multiple instances of the VSI, however. We'd have to change some of the right-click options to allow you to specify which instance of the VSI you wanted to overplot data on (for PeaksWorkspaces). Alternately, we could disable the VSI option for PeaksWorkspace, and only allow them to be dragged-dropped over the top of the specific VSI instance.

[Nick Draper]

At this point I think it is important to maintain the S in VSI. I think it is worth creating a wiki example page that show how to compare two workspaces using options 1 and 2. This we can use to show people that are not familiar the step by step approaches for a way around this issue.

At this point I think approaches 3 and 4 are not necessary.

[Stuart Campbell]

This ticket has been transferred to github issue ​7925