Matching Spectra in ReflectometryReductionOne

[Owen Arnold]

ReflectometryReductionOne has the ability to accept Transmission Workspaces for normalisation. The current behaviour is that the spectrum numbers are taken from the numerator workspace, and used to find and crop the correct spectra out of the denominator (transmission) workspace. If spectrum numbers cannot be found that match up, the algorithm exits without completing.

The behaviour requested by Tim Charlton is that we have an optional less-severe penalty for having mismatched spectrum numbers and allow the division to proceed on the basis of workspace index matching. This would be an optional switch, which would be On by default, and would still log a warning message that users could heed.

Switch would be something like 'StrictSpectrumChecking'. Users would have to actively disable it.

The code this will affect is in ReflectometryReductionOne, where createWorkspaceIndexListFromDetectorWorkspace is used.

[Owen Arnold]

refs #8789. New strict spectrum checking option.

Warn if turned off. Fail if turned on (default). Unit tests extended and updated for this feature.

Changeset: 8095434a103f43484ca723e3946c13e45adc6c6a

[Owen Arnold]

Tester:

The following shows this working. With StrictSpectrumChecking=False, a warning is emitted indicating that the spectrum numbers between the transmission run and the detector run do not match up.

config['default.instrument'] = 'INTER'
trans1 = LoadISISNexus(Filename='13463', OutputWorkspace='13463')
trans2 = LoadISISNexus(Filename='13464', OutputWorkspace='13464')
run = LoadISISNexus(Filename='13460', OutputWorkspace='13460')
 
incidentAngle = 0.7

 
transmission = CreateTransmissionWorkspaceAuto(Params=[1.5, 0.02, 17],
                                           StartOverlap=10.0, 
                                           EndOverlap=12.0, 
                                           FirstTransmissionRun=trans1, 
                                           SecondTransmissionRun=trans2,
                                           ProcessingInstructions='1,2' # Deliberately doing someing bad here!
                                           )
                                           
                           
 
qOut, lamOut, thetaOut = ReflectometryReductionOneAuto(InputWorkspace=run, ThetaIn=incidentAngle, FirstTransmissionRun=transmission, StrictSpectrumChecking=False)
 

Now run the same script with the StrictSpectrumChecking=True. You should get a runtime error indicating that spectrum numbers do not match up.

Now run the same code, but delete the StrictSpectrumChecking option altogether. You should get the same behaviour as having it equal to True.

[Owen Arnold]

refs #8789. Improve documentation.

Changeset: 2d6f6c0ba751da5f34b4e8a4086d54c8eb0beed8

[Karl Palmen]

Merge remote-tracking branch 'origin/feature/8789_spectra_matching_option'

Full changeset: ​9f8ac1798b6d4522b19573ed0b2f1ee9beb7b69d

[Stuart Campbell]

This ticket has been transferred to github issue ​9633