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ConvertAxesToRealSpace v1

Summary

Converts the spectrum and TOF axes to real space values, integrating the data in the process

See Also

ConvertSpectrumAxis, ConvertUnits

Properties

Name	Direction	Type	Default	Description
InputWorkspace	Input	MatrixWorkspace	Mandatory	An input workspace.
OutputWorkspace	Output	Workspace2D	Mandatory	An output workspace.
VerticalAxis	Input	string	y	What will be the vertical axis ? Allowed values: [‘x’, ‘y’, ‘z’, ‘r’, ‘theta’, ‘phi’, ‘2theta’, ‘signed2theta’]
HorizontalAxis	Input	string	2theta	What will be the horizontal axis? Allowed values: [‘x’, ‘y’, ‘z’, ‘r’, ‘theta’, ‘phi’, ‘2theta’, ‘signed2theta’]
NumberVerticalBins	Input	number	100	The number of bins along the vertical axis.
NumberHorizontalBins	Input	number	100	The number of bins along the horizontal axis.

LET converted to X and Y

Description

This converts the workspace into a 2D view of real space detector positions based on the detector positions. This is intended for rapid visualization and has been optimized for speed for use in Live data streams. If the data provided has data binned in Time of flight or any other unit this will be integrated into a single value per detector, before converting to the selected detector and rebinning to the new grid. The output grid is based in the maximum and minimum values of the detectors for axes selected, and the number of bins selected. The rebinning is simply based on centre point rebinning, and as such can be prone to moire based artefacts, however it is fast.

As the rebinning approach is simple centre point rebinning then the quality of the final plot is sensitive to the number of bins selected for each axis, too many will cause gaps between the detectors, and too few will cause overlap in certain bins.

LET in 2Theta and Y

Axes Units

Name	Units	Description
x, y ,z	meters	The absolute position of the detector as defined in the instrument definition.
r	meters	The absolute position of the detector in spherical coordinates, relative to 0,0,0 as defined in the instrument definition.
theta, phi	degrees
2theta	radians	The theta position of the detector relative to sample position and the beam direction. if the sample is at 0,0,0 and the beam direction matches, then this will match theta above.
signed2Theta	radians	Similar to 2theta, but with a sign calculated relative to the instrument reference frame, with the upper quadrants taking the positive value

Usage

Example - ConvertAxesToRealSpace

ws = CreateSampleWorkspace(BankPixelWidth=20)
#move the 2nd bank to a better position
MoveInstrumentComponent(ws,"bank2",X=0.2,Z=-5,RelativePosition=True)

wsOut = ConvertAxesToRealSpace(ws,"y","2theta",20,20)

# Print the result
print("The output workspace has axes of {} with {} bins".format(wsOut.getAxis(1).getUnit().caption(), wsOut.getNumberHistograms()))
print("and {} with {} bins.".format(wsOut.getAxis(0).getUnit().caption(), wsOut.blocksize()))

Output:

The output workspace has axes of y with 20 bins
and 2theta with 20 bins.

Categories: AlgorithmIndex | Transforms\Units | Transforms\Axes

Source

C++ header: ConvertAxesToRealSpace.h

C++ source: ConvertAxesToRealSpace.cpp