Include background in fitting data with ComptonScatteringCountRate

[Nick Draper]

Moved to backlog at the code freeze for R2.6

[Martyn Gigg]

Refactor ComptonScattering to allow for a background.

The constraint matrices need to expand if a background is to be included. Refs #7492

Changeset: 5f80950633883e4e951883667f6ea7231796ee45

[Martyn Gigg]

Allow ComptonScatteringCountRate to include a background.

Refs #7492

Changeset: e7dabe86db12c6a30b0e646b8dbe6f50419943ed

[Martyn Gigg]

Alter ComptonProfile to require input data in seconds.

Avoids having to implement custom background functions that understand that the data must be in seconds. Refs #7492

Changeset: 0eb39f8df6063683d500e3c1e6dc252ecc5d3b04

[Martyn Gigg]

Added AugmentedLagrangianOptimizer

Used for solving minimization problems subject to constraints. Refs #7492

Changeset: 5502ad26a54c56ee091cede74b970dea4fc54e39

[Martyn Gigg]

Use AugmentedLagrangian optimizer in ComptonScatterCountRate

It is better at dealing with larger scale objective functions when the background is included. Refs #7492

Changeset: edf74d130ff6166b316236035a9e023b0e2f97ff

[Martyn Gigg]

Add Vesuvio fit test for when Kfse is free parameter.

Refs #7492

Changeset: e1d45b8e34f789ea0be86338b89389a8ee4ac3a4

[Martyn Gigg]

Update Vesuvio system tests due to optimizer changes.

Refs #7492

Changeset: 91427aeb88bfc25fd3017f73a7345e448d3d916f

[Martyn Gigg]

Add Vesuvio Fitting test including a background.

Refs #7492

Changeset: d30019d6990d0272146d9369519a7a4c472f5fea

[Martyn Gigg]

Branch: feature/7492_background_in_compton_scattering

Tester: The following script should run the fitting as the Vesuvio guys do. The systemtests/Data directory will need to be in the data search path.

function_str = \
        "composite=ComptonScatteringCountRate,NumDeriv=1,IntensityConstraints=\"Matrix(1|3)0|-1|3\";"\
        "name=GramCharlierComptonProfile,WorkspaceIndex=0,Mass=1.007940,HermiteCoeffs=1 0 1;"\
        "name=GaussianComptonProfile,WorkspaceIndex=0,Mass=27.000000;"\
        "name=GaussianComptonProfile,WorkspaceIndex=0,Mass=91.000000;name=Polynomial,n=1,A0=0,A1=0"
    # Run fit
    _do_fit(function_str, k_is_free=True)

def _do_fit(function_str, k_is_free):
    """
    Run the Vesuvio . If k_is_free is False then it is fixed to f0.Width*sqrt(2)/12
    
    """
    LoadVesuvio(Filename='14188-14190',OutputWorkspace='raw_ws',SpectrumList='135',Mode='SingleDifference',
                InstrumentParFile=r'IP0005.dat')
    CropWorkspace(InputWorkspace='raw_ws',OutputWorkspace='raw_ws',XMin=50,XMax=562)
    # Convert to seconds
    ScaleX(InputWorkspace='raw_ws',OutputWorkspace='raw_ws',Operation='Multiply',Factor=1e-06)
    
    if k_is_free:
        ties_str = "f1.Width=10.000000,f2.Width=25.000000"
    else:
        ties_str = "f1.Width=10.000000,f2.Width=25.000000,f0.FSECoeff=f0.Width*sqrt(2)/12"

    constraints_str = "2.000000 < f0.Width < 7.000000"
    
    Fit(InputWorkspace='raw_ws',Function=function_str,Ties=ties_str,Constraints=constraints_str,
        Output=WS_PREFIX, CreateOutput=True,OutputCompositeMembers=True,MaxIterations=5000,
        Minimizer="Levenberg-Marquardt,AbsError=1e-08,RelError=1e-08")
    # Convert to microseconds
    ScaleX(InputWorkspace=WS_PREFIX + '_Workspace',OutputWorkspace=WS_PREFIX + '_Workspace',Operation='Multiply',Factor=1e0

It should produce a reasonable fit with a table of parameters that includes f4.A0 & f4.A1 that relate to the background. Ultimate confirmation of the validity of the results has to lie with the Vesuvio guys but we need it in master to get that far.

[Martyn Gigg]

Fix silly copy-and-paste error in VesuvioTest reference file

Refs #7492

Changeset: 21d391444e8de500a8dbaf7eaf1aa59eec4f47a9

[Martyn Gigg]

Relax tolerance on windows/mac for vesuvio tests.

The results are still acceptable they just differ slightly (my guess is the GSL) from Linux where the reference file was created. Refs #7492

Changeset: ff671edd32f208431096c6571904362af4c245d5

[Martyn Gigg]

Relax Mac tolerance. Refs #7492

Changeset: 69ffa416a305000821139628aed51e5792441707

[Gesner Passos]

Merge remote-tracking branch 'origin/feature/7492_background_in_compton_scattering'

Full changeset: ​7e62579abce0e37800ffe211d15d066674ae23e6

[Gesner Passos]

The results are sensible, and the implementation is well planed. Besides, the extension of the systemtests seems quite reasonable.

[Gesner Passos]

Merge remote-tracking branch 'origin/feature/7492_background_in_compton_scattering'

Full changeset: ​9604f8754c888624a383c1f1982499ebe73e9fcd

[Martyn Gigg]

Relax Vesuvio fit tolerance for 32-bit Windows.

Refs #7492

Changeset: adce86757d1ae37dac071f84bdcca9aab5f4fc22

[Martyn Gigg]

Fix VeusvioTest syntax

Refs #7492

Changeset: 544df9cf16cc5907dff93dc281e35c2d059bb6cd

[Martyn Gigg]

Merge remote-tracking branch 'origin/feature/7492_background_in_compton_scattering'

Full changeset: ​e18f99097c78981dcb3aae61991d842d3d4f2367

[Stuart Campbell]

This ticket has been transferred to github issue ​8337