CalculateCoverageDGS v1

../_images/CalculateCoverageDGS-v1_dlg.png

CalculateCoverageDGS dialog.

Summary

Calculate the reciprocal space coverage for direct geometry spectrometers

Properties

Name Direction Type Default Description
InputWorkspace Input MatrixWorkspace Mandatory An input workspace.
Q1Basis Input dbl list 1,0,0 Q1 projection direction in the x,y,z format. Q1, Q2, Q3 must not be coplanar
Q2Basis Input dbl list 0,1,0 Q2 projection direction in the x,y,z format. Q1, Q2, Q3 must not be coplanar
Q3Basis Input dbl list 0,0,1 Q3 projection direction in the x,y,z format. Q1, Q2, Q3 must not be coplanar
IncidentEnergy Input number Optional Incident energy. If set, will override Ei in the input workspace
Dimension1 Input string Q1 Dimension to bin or integrate. Allowed values: [‘Q1’, ‘Q2’, ‘Q3’, ‘DeltaE’]
Dimension1Min Input number Optional Dimension1 minimum value. If empty will take minimum possible value.
Dimension1Max Input number Optional Dimension1 maximum value. If empty will take maximum possible value.
Dimension1Step Input number Optional Dimension1 step size. If empty the dimension will be integrated between minimum and maximum values
Dimension2 Input string Q2 Dimension to bin or integrate. Allowed values: [‘Q1’, ‘Q2’, ‘Q3’, ‘DeltaE’]
Dimension2Min Input number Optional Dimension2 minimum value. If empty will take minimum possible value.
Dimension2Max Input number Optional Dimension2 maximum value. If empty will take maximum possible value.
Dimension2Step Input number Optional Dimension2 step size. If empty the dimension will be integrated between minimum and maximum values
Dimension3 Input string Q3 Dimension to bin or integrate. Allowed values: [‘Q1’, ‘Q2’, ‘Q3’, ‘DeltaE’]
Dimension3Min Input number Optional Dimension3 minimum value. If empty will take minimum possible value.
Dimension3Max Input number Optional Dimension3 maximum value. If empty will take maximum possible value.
Dimension3Step Input number Optional Dimension3 step size. If empty the dimension will be integrated between minimum and maximum values
Dimension4 Input string DeltaE Dimension to bin or integrate. Allowed values: [‘Q1’, ‘Q2’, ‘Q3’, ‘DeltaE’]
Dimension4Min Input number Optional Dimension4 minimum value. If empty will take minimum possible value.
Dimension4Max Input number Optional Dimension4 maximum value. If empty will take maximum possible value.
Dimension4Step Input number Optional Dimension4 step size. If empty the dimension will be integrated between minimum and maximum values
OutputWorkspace Output Workspace Mandatory A name for the output data MDHistoWorkspace.

Description

The algorithm calculates what part of the reciprocal space is covered by direct geometry spectrometers. It is supposed to be used in planning tools. The input workspace should contain the incident energy log, a goniometer, and the UB matrix. The incident energy can be overwritten by setting the IncidentEnergy parameter. The output is an MDHisto workspace. You can visualize it with SliceViewer.

The parameters Q1Basis, Q2Basis, Q3Basis can be used to look at different directions in the reciprocal space, such as [H,H,0]

DimensionI, where I is from 1 to 4, allows one to select in which order Q1, Q2, Q3, DeltaE are stored in the output workspace. The algorithm will complain if you select the same dimension twice. For each dimension one can define minimum, maximum, and step size. If no minimum/maximum are set for DeltaE, these are chosen to be +/-Ei. If not specified, minimum/maximum for the Q dimensions are calculated based on the instrument geometry, incident energy, minimum/maximum for DeltaE, and lattice parameters.

The algorithm calculates detector trajectories in the reciprocal space and sets to 1 the coresponding points in the output workspace. All other points are 0.

Usage

Note

To run these usage examples please first download the usage data, and add these to your path. In MantidPlot this is done using Manage User Directories.

Example - CalculateCoverageDGS

w=Load(Filename="CNCS_7860")
w=ConvertUnits(InputWorkspace=w,Target='DeltaE', EMode='Direct', EFixed='3')
SetGoniometer(Workspace=w, Axis0='30,0,1,0,1')
SetUB(Workspace=w, a='2', b='2', c='2')
w=Rebin(InputWorkspace=w, Params='-3,0.1,3', PreserveEvents='0')
coverage=CalculateCoverageDGS(InputWorkspace=w, IncidentEnergy=3,
    Dimension1Min=-1, Dimension1Max=1, Dimension1Step=0.02,
    Dimension2Min=-1, Dimension2Max=1, Dimension2Step=2,
    Dimension3Min=-1, Dimension3Max=1, Dimension3Step=2,
    Dimension4Min=0, Dimension4Max=3, Dimension4Step=0.1)

# Print the result
print "You cover %i MD bins out of %i" %(coverage.getSignalArray().sum(),coverage.getSignalArray().size)

Output:

You cover 506 MD bins out of 3000

Categories: Algorithms | Inelastic\Planning | MDAlgorithms\Planning