BinMD/SliceMD info (Beta Test issue)

[Owen Arnold]

Following mantid-help beta test report by Jon Taylor 4th/May/2015 regarding the sliceviewer.

The problem is that for axis-aligned cuts, you can actually reduce the dimensionality of the output workspace compared to the input by ommiting the axis aligned binning information for some dimensions. If you try to slice again, then BinMD correctly identifies that the original workspace does not have the same dimensionality as the output. The following shows how this sort of slicing can be done.

CreateMDWorkspace(Dimensions=3, Extents='-10,10,-10,10,-10,10', Names='Q_lab_x,Q_lab_y,Q_lab_z', Units='A,A,A', OutputWorkspace='WS')
FakeMDEventData(InputWorkspace='WS', PeakParams='10000,0,0,0,0.1', RandomizeSignal=True)
BinMD(InputWorkspace='WS', AlignedDim0='Q_lab_x,-10,10,10', AlignedDim1='Q_lab_y,-10,10,10', OutputWorkspace='binned')

print 'Dims before', mtd['WS'].getNumDims()
print 'Dims after', mtd['binned'].getNumDims()

[Owen Arnold]

After discussion with Jon Taylor, it was agreed that the best course of action would be to warn if this sort of cut was being made.

[Owen Arnold]

refs #11696. Emit warning

Changeset: e0a07b02ea758cf16bc1d8f9ae722545681fc9ca

[Owen Arnold]

This is being verified as ​pull request #711.

[Anton Piccardo-Selg]

The script produces a rebinned output and creates the warning regarding lower dimensional cuts.

[Anton Piccardo-Selg]

Merge pull request #711 from mantidproject/11696_slicing_algorithm_warning

BinMD/SliceMD axis-aligned warning

Full changeset: ​8ad9300cb3eeb852c30c22e1fcee7a925b20eec6

[Stuart Campbell]

This ticket has been transferred to github issue ​12534