Implement LeBail fitting of cubic lattice

[wdzhou]

This ticket is blocked by :

• TRAC5651

Implement LeBail fitting in Mantid. It will support sample of cubic lattice structure in this task.

==== Test Instruction ====
Please run the following script to prepare for Le Bail Fit. The data files can be found in systemtests/data/

# Import data
LoadAscii(Filename='4844b1.inp',OutputWorkspace='4844b1',Unit='TOF')

# Create some table workspaces for staring values
CreateLeBailFitInput(Instrument='NOMAD',ReflectionsFile='LB4844b1.hkl',
   FullprofParameterFile='2011B_HR60b1.irf',LatticeConstant='4.1568899999999998',
   InstrumentParameterWorkspace='Peak4844',BraggPeakParameterWorkspace='HKL4844')

# Fit for background of the diffraction pattern
ProcessBackground(InputWorkspace='4844b1',OutputWorkspace='4844b1_bkgd',
    Options='SelectBackgroundPoints',LowerBound='5053',UpperBound='49387',
    BackgroundType='Chebyshev',
    BackgroundPoints='5000,6500,8951,10670,15231,16943,24887,33527,40200,45110,49725',
    NoiseTolerance='20')

Fit(Function='name=Polynomial,n=6,A0=0,A1=0,A2=0,A3=0,A4=0,A5=0,A6=0',
    InputWorkspace='4844b1_bkgd',MaxIterations='1000',
    Minimizer='Levenberg-MarquardtMD',
    CreateOutput='1',Output='4844b_polybkgd',
    StartX='2277.27',EndX='49988.900000000001')

# Calculate peak heights with Le Bail algorithm
LeBailFit(InputWorkspace='4844b1',OutputWorkspace='4844b1_cal',
    InputParameterWorkspace='Peak4844',OutputParameterWorkspace='Temp1',
    InputHKLWorkspace='HKL4844',OutputPeaksWorkspace='Temp2',Function='Calculation',
    BackgroundFunctionOrder='6',BackgroundParametersWorkspace='4844b_polybkgd_Parameters',
    UseInputPeakHeights='0',PeakRadius='8')

The input instrument resolution file already contains well-fitted data. Thus for testing purpose, some parameter value can be shifted.

# Fix all the parameters
UpdatePeakParameterTableValue(InputWorkspace='Peak4844',Column='FitOrTie',NewStringValue='t')
# Change value of Alph1
UpdatePeakParameterTableValue(InputWorkspace='Peak4844',ParameterNames='Alph1',NewFloatValue='6')
# Flag Alph1 to be fit
UpdatePeakParameterTableValue(InputWorkspace='Peak4844',Column='FitOrTie',ParameterNames='Alph1',NewStringValue='f')

Then LeBailFit() can be called as

LeBailFit(InputWorkspace='4844b1',OutputWorkspace='4844b1_fitalph1',InputParameterWorkspace='Peak4844',OutputParameterWorkspace='Peak4844X',InputHKLWorkspace='HKL4844',OutputPeaksWorkspace='HKL4844X',BackgroundFunctionOrder='6',BackgroundParametersWorkspace='4844b_polybkgd_Parameters',UseInputPeakHeights='0',PeakRadius='8',Minimizer='SteepestDescent')

[wdzhou]

This issue was originally trac ticket 5306