DefineGaugeVolume dialog.
Table of Contents
Defines a geometrical shape object to be used as the gauge volume in the AbsorptionCorrection algorithm.
| Name | Direction | Type | Default | Description |
|---|---|---|---|---|
| Workspace | InOut | MatrixWorkspace | Mandatory | The workspace with which to associate the defined gauge volume |
| ShapeXML | Input | string | Mandatory | The XML that describes the shape of the gauge volume |
Intended for use on data from engineering beamlines, this algorithm creates a shape object for use as the ‘gauge volume’ (i.e. the portion of the sample that is visible to the detectors in a given run) of a larger sample in the AbsorptionCorrection v1 algorithm. The sample shape will also need to be defined using, e.g., the CreateSampleShape v1 algorithm. Shapes are defined using XML descriptions that can be found here.
Internally, this works by attaching the XML string (after validating it) to a property called “GaugeVolume” on the workspace’s Run object.
Example: A simple spherical sample with a cuboid guage volume
#setup the sample shape
sphere = '''<sphere id="sample-sphere">
<centre x="0" y="0" z="0"/>
<radius val=".2" />
</sphere>'''
ws = CreateSampleWorkspace("Histogram",NumBanks=1,BankPixelWidth=1)
ws = ConvertUnits(ws,"Wavelength")
ws = Rebin(ws,Params=[1])
CreateSampleShape(ws,sphere)
SetSampleMaterial(ws,ChemicalFormula="V")
#setup the guage volume
cuboid = '''<cuboid id="shape">
<left-front-bottom-point x="0.01" y="-0.1" z="0.0" />
<left-front-top-point x="0.01" y="-0.1" z="0.02" />
<left-back-bottom-point x="-0.01" y="-0.1" z="0.0" />
<right-front-bottom-point x="0.01" y="0.1" z="0.0" />
</cuboid>'''
DefineGaugeVolume(ws,cuboid)
#restrict the number of wavelength points to speed up the example
wsOut = AbsorptionCorrection(ws, NumberOfWavelengthPoints=5, ElementSize=2)
print "The created workspace has one entry for each spectra: %i" % wsOut.getNumberHistograms()
Output:
The created workspace has one entry for each spectra: 1
Categories: Algorithms | Sample