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CreateUserDefinedBackground v1

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Summary

Creates a workspace of background data from a user-supplied set of points. This workspace can then be subtracted from the original data.

See Also

RemoveBackground, CalculatePolynomialBackground

Properties

Name	Direction	Type	Default	Description
InputWorkspace	Input	MatrixWorkspace	Mandatory	Input workspace containing data and background
BackgroundPoints	Input	TableWorkspace	Mandatory	Table containing user-defined background points
OutputBackgroundWorkspace	Output	MatrixWorkspace	Mandatory	Workspace containing background to be subtracted

Description

Given an input workspace containing data with a background and a table of user-selected points defining the background, creates a new workspace containing background data that can be subtracted from the original data.

The background is constructed using linear interpolation at the same X values as the input workspace.

Usage

Example - CreateUserDefinedBackground

# Create data: background + peak
dataX = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
background = [0, 5, 10, 15, 20, 25, 30, 35, 40, 45]
peak = [0, 1, 4, 1, 0, 0, 0, 0, 0, 0]
dataY = [a + b for a, b in zip(background, peak)]
dataWS = CreateWorkspace(dataX, dataY)

# Create table of user-supplied background points
# In real use this would be done via the GUI
background_points = CreateEmptyTableWorkspace()
background_points.addColumn("double", "X", 1)
background_points.addColumn("double", "Y", 2)
for i in range(10):
   background_points.addRow([dataX[i], background[i]])

# Create background workspace and subtract it from data
backgroundWS = CreateUserDefinedBackground(InputWorkspace=dataWS, BackgroundPoints=background_points)
peakWS = Minus(dataWS, backgroundWS)


# Check that workspace matches expected peak
expected = CreateWorkspace(dataX, peak)
result, messages = CompareWorkspaces(peakWS, expected)
print("Workspaces match: {}".format(result))

Output:

Workspaces match: True

Categories: AlgorithmIndex | CorrectionFunctions\BackgroundCorrections

Source

C++ header: CreateUserDefinedBackground.h

C++ source: CreateUserDefinedBackground.cpp