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VesuvioPreFit v1¶

../_images/ImageNotFound.png — Enable screenshots using DOCS_SCREENSHOTS in CMake¶

Summary ¶

Apply preprocessing steps to loaded vesuvio data

Properties ¶

Name	Direction	Type	Default	Description
InputWorkspace	Input	MatrixWorkspace	Mandatory	Input TOF workspace from LoadVesuvio
Smoothing	Input	string	Neighbour	Defines the smoothing method. Allowed values: [‘Neighbour’, ‘None’]
SmoothingOptions	Input	string	NPoints=3	Override the default smoothing options
BadDataError	Input	number	1000000	Mask any data point with an error greater than this value. Set to 0 to turn it off
OutputWorkspace	Output	MatrixWorkspace	Mandatory	The name of the output workspace

Description ¶

Applies the preprocessing steps to loaded vesuvio data before it is fitted. These steps include: - Smoothing the data - Masking bad detectors

Usage ¶

Example - VesuvioPreFit

###### Simulates LoadVesuvio with spectrum number 135-136 #################
tof_ws = CreateSimulationWorkspace(Instrument='Vesuvio',BinParams=[50,0.5,562],UnitX='TOF')
tof_ws = CropWorkspace(tof_ws,StartWorkspaceIndex=134,EndWorkspaceIndex=135) # index one less than spectrum number
tof_ws = ConvertToPointData(tof_ws)
SetInstrumentParameter(tof_ws, ParameterName='t0',ParameterType='Number',Value='0.5')
SetInstrumentParameter(tof_ws, ParameterName='sigma_l1', ParameterType='Number', Value='0.021')
SetInstrumentParameter(tof_ws, ParameterName='sigma_l2', ParameterType='Number', Value='0.023')
SetInstrumentParameter(tof_ws, ParameterName='sigma_tof', ParameterType='Number', Value='0.3')
SetInstrumentParameter(tof_ws, ParameterName='sigma_theta', ParameterType='Number', Value='0.028')
SetInstrumentParameter(tof_ws, ParameterName='hwhm_lorentz', ParameterType='Number', Value='24.0')
SetInstrumentParameter(tof_ws, ParameterName='sigma_gauss', ParameterType='Number', Value='73.0')
# Algorithm allows separate parameters for the foils
SetInstrumentParameter(tof_ws, ComponentName='foil-pos0', ParameterName='hwhm_lorentz',
                       ParameterType='Number', Value='144.0')
SetInstrumentParameter(tof_ws, ComponentName='foil-pos0', ParameterName='sigma_gauss',
                       ParameterType='Number', Value='20.0')
SetInstrumentParameter(tof_ws, ComponentName='foil-pos1', ParameterName='hwhm_lorentz',
                       ParameterType='Number', Value='144.0')
SetInstrumentParameter(tof_ws, ComponentName='foil-pos1', ParameterName='sigma_gauss',
                       ParameterType='Number', Value='20.0')

###########################################################################

pre_fit_workspace = VesuvioPreFit(Inputworkspace=tof_ws, Smoothing="Neighbour",
                                  SmoothingOptions="NPoints=3", BadDataError=-1)