FindPeaksMD: find the detector for a found peak

[Janik Zikovsky]

So that the PeaksWorkspace has the bank, row, col to save to ISAW.

[Janik Zikovsky]

In [13775]:

Refs #3521: Utility function in instrument ray tracer.

[Janik Zikovsky]

In [13777]:

Refs #3521: MDEWFindPeaks fills in the detector, row, col of the peaks found where possible. SaveIsawPeaks works with the output.

[Janik Zikovsky]

In [13782]:

Fixes #3521: MDEWFindPeaks finds the detector and row and column.

[Stuart Campbell]

It is impossible to add an instrument to an MDworkspace (as it doesn't show up in the list of workspaces when you run LoadInstrument), so the FindPeaksMD just returns an error.

This is more likely a problem with the Workspace validator that only shows 'valid' workspaces.

[Janik Zikovsky]

Keep in mind that FindPeaksMD works off of MDEventWorkspaces, and not Alex's MDworkspaces. See for example this script:

# Basic parameters
filename = "TOPAZ_3131_event.nxs"
#Name of the workspaces to create
ws = "TOPAZ_3131"

# Load the original data
LoadEventNexus(Filename=filename,OutputWorkspace=ws)

# Convert to reciprocal space, in the sample frame
ConvertToDiffractionMDWorkspace(InputWorkspace=ws,OutputWorkspace=ws+'_MD',
		OutputDimensions='Q (sample frame)',LorentzCorrection='1')
		
# Find peaks
FindPeaksMD(InputWorkspace=ws+'_MD',MaxPeaks='50',OutputWorkspace=ws+'_peaks')

Also note that the instrument MUST have RectangularDetectors in order to find a meaningful row/column.

[Stuart Campbell]

I do get some peaks...

[Stuart Campbell]

This ticket has been transferred to github issue ​4368