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MDNormSCD v1¶
Summary¶
Calculate normalization for an MDEvent workspace for single crystal diffraction.
See Also¶
Properties¶
Name |
Direction |
Type |
Default |
Description |
|---|---|---|---|---|
InputWorkspace |
Input |
Mandatory |
An input MDWorkspace. |
|
AlignedDim0 |
Input |
string |
Binning parameters for the 0th dimension. Enter it as a comma-separated list of values with the format: ‘name,minimum,maximum,number_of_bins’. Leave blank for NONE. |
|
AlignedDim1 |
Input |
string |
Binning parameters for the 1th dimension. Enter it as a comma-separated list of values with the format: ‘name,minimum,maximum,number_of_bins’. Leave blank for NONE. |
|
AlignedDim2 |
Input |
string |
Binning parameters for the 2th dimension. Enter it as a comma-separated list of values with the format: ‘name,minimum,maximum,number_of_bins’. Leave blank for NONE. |
|
AlignedDim3 |
Input |
string |
Binning parameters for the 3th dimension. Enter it as a comma-separated list of values with the format: ‘name,minimum,maximum,number_of_bins’. Leave blank for NONE. |
|
AlignedDim4 |
Input |
string |
Binning parameters for the 4th dimension. Enter it as a comma-separated list of values with the format: ‘name,minimum,maximum,number_of_bins’. Leave blank for NONE. |
|
AlignedDim5 |
Input |
string |
Binning parameters for the 5th dimension. Enter it as a comma-separated list of values with the format: ‘name,minimum,maximum,number_of_bins’. Leave blank for NONE. |
|
FluxWorkspace |
Input |
Mandatory |
An input workspace containing momentum dependent flux. |
|
SolidAngleWorkspace |
Input |
Mandatory |
An input workspace containing momentum integrated vanadium (a measure of the solid angle). |
|
SkipSafetyCheck |
Input |
boolean |
False |
If set to true, the algorithm does not check history if the workspace was modified since theConvertToMD algorithm was run, and assume that the elastic mode is used. |
TemporaryNormalizationWorkspace |
Input |
IMDHistoWorkspace |
An input MDHistoWorkspace used to accumulate normalization from multiple MDEventWorkspaces. If unspecified a blank MDHistoWorkspace will be created. |
|
TemporaryDataWorkspace |
Input |
IMDHistoWorkspace |
An input MDHistoWorkspace used to accumulate data from multiple MDEventWorkspaces. If unspecified a blank MDHistoWorkspace will be created. |
|
OutputWorkspace |
Output |
Mandatory |
A name for the output data MDHistoWorkspace. |
|
OutputNormalizationWorkspace |
Output |
Mandatory |
A name for the output normalization MDHistoWorkspace. |
Description¶
The algorithm calculates a normalization MD workspace for single crystal diffraction experiments. Trajectories of each detector in reciprocal space are calculated, and the flux is integrated between intersections with each MDBox. A brief introduction to the multi-dimensional data normalization can be found here.
The algorithm MDNormSCDPreprocessIncoherent can be used to process Vanadium data for the Solid Angle and Flux workspaces.
Note
As of Release 4.0.0, the algorithm can handle merged MD workspaces. Make sure all original MDEvent workspaces have the same dimensions
Usage¶
Example - MDNormSCD
try:
# Setting up the workspaces containing information about the flux and the solid angle (from a vanadium run)
rawVan=Load(Filename=r'TOPAZ_7892_event.nxs')
rawVan=ConvertUnits(InputWorkspace=rawVan,Target='Momentum')
MaskBTP(Workspace=rawVan,Bank="10-16,19-21,23-25,29-35,40-46,49-57,59")
MaskBTP(Workspace=rawVan,Pixel="0-9,246-255")
MaskBTP(Workspace=rawVan,Tube="0-9,246-255")
rawVan=CropWorkspace(InputWorkspace=rawVan,XMin='1.85',XMax='10')
#Solid angle
sa=Rebin(InputWorkspace=rawVan,Params='1.85,10,10',PreserveEvents='0')
SaveNexus(InputWorkspace=sa, Filename="/home/3y9/Desktop/TOPAZ/solidAngle.nxs")
#flux
flux=GroupDetectors(InputWorkspace=rawVan,MapFile=r'/home/3y9/Desktop/TOPAZ/grouping.xml')
DeleteWorkspace(rawVan)
flux=CompressEvents(InputWorkspace=flux,Tolerance=1e-4)
flux=Rebin(InputWorkspace=flux,Params='1.85,10,10')
for i in range(flux.getNumberHistograms()):
el=flux.getSpectrum(i)
el.divide(flux.readY(i)[0],0)
flux=Rebin(InputWorkspace=flux,Params='1.85,10,10')
flux=IntegrateFlux(flux)
SaveNexus(InputWorkspace=flux, Filename="/home/3y9/Desktop/TOPAZ/spectra.nxs")
#data
#If you have multiple workspaces, add separately the output workspaces, and separately the
#output normalization workspaces, then divide the two sums
runs = range(7985,7995,1)
mdout = None
mdnorm = None
for run in runs:
try:
MDdata = LoadMD(Filename="/home/3y9/Desktop/TOPAZ/MDdata_"+str(run)+".nxs")
except:
data=Load(Filename='TOPAZ_'+str(run)+'_event.nxs')
data=ConvertUnits(InputWorkspace=data,Target='Momentum')
MaskBTP(Workspace=data,Bank="10-16,19-21,23-25,29-35,40-46,49-57,59")
MaskBTP(Workspace=data,Pixel="0-9,246-255")
MaskBTP(Workspace=data,Tube="0-9,246-255")
data=CropWorkspace(InputWorkspace=data,XMin='1.85',XMax='10')
data=Rebin(InputWorkspace=data,Params='1.85,10,10')
LoadIsawUB(InputWorkspace=data,Filename=r'7995.mat')
MDdata=ConvertToMD(InputWorkspace=data,QDimensions="Q3D",dEAnalysisMode="Elastic",
Q3DFrames="HKL",QConversionScales="HKL",
MinValues="-10,-10,-10",Maxvalues="10,10,10")
SaveMD(InputWorkspace=MDdata, Filename="/home/3y9/Desktop/TOPAZ/MDdata_"+str(run)+".nxs")
#running the algorithm
mdout, mdnorm = MDNormSCD(InputWorkspace='MDdata',
AlignedDim0='[H,0,0],-8,8,100',
AlignedDim1='[0,K,0],-8,8,100',
AlignedDim2='[0,0,L],-8,8,100',
FluxWorkspace=flux,
SolidAngleWorkspace=sa,
TemporaryDataWorkspace=mdout,
TemporaryNormalizationWorkspace=mdnorm)
normalized=DivideMD('mdout','mdnorm')
except:
pass
References¶
The source for how this calculation is done is
T.M. Michels-Clark, A.T. Savici, V.E. Lynch, X.P. Wang and C.M. Hoffmann Expanding Lorentz and spectrum corrections to large volumes of reciprocal space for single-crystal time-of-flight neutron diffraction. J Appl Crystallogr 49.2 (2016) doi: 10.1107/S1600576716001369
Categories: AlgorithmIndex | MDAlgorithms\Normalisation
Source¶
C++ header: MDNormSCD.h
C++ source: MDNormSCD.cpp