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Symmetrise v1¶

../_images/ImageNotFound.png — Enable screenshots using DOCS_SCREENSHOTS in CMake¶

Summary ¶

Make asymmetric workspace data symmetric.

Properties ¶

Name	Direction	Type	Default	Description
InputWorkspace	Input	MatrixWorkspace	Mandatory	Sample to run with
SpectraRange	Input	long list		Range of spectra to symmetrise (defaults to entire range if not set)
XMin	Input	number	0	X value marking lower limit of curve to copy
XMax	Input	number	0	X value marking upper limit of curve to copy
OutputWorkspace	Output	MatrixWorkspace	Mandatory	Name to call the output workspace.
OutputPropertiesTable	Output	TableWorkspace		Name to call the properties output table workspace.

Description ¶

Symmetrise takes a matrix workspace containing asymmetric data and makes it symmetrical around x=0 by reflecting a given section of the right hand side (positive) on the left hand side (negative).

Two values, XMin and XMax, are chosen to specify the section of the positive side of the curve to be reflected onto the negative side, the sample curve is cropped at XMax ensuring that the symmetrised curve has a symmetrical X range.

Usage ¶

Example - Running Symmetrise on an asymmetric workspace.

import numpy as np

# create an asymmetric line shape
def rayleigh(x, sigma):
  return (x / sigma ** 2) * np.exp(-x ** 2 / (2 * sigma ** 2))

data_x = np.arange(0, 10, 0.01)
data_y = rayleigh(data_x, 1)

sample_ws = CreateWorkspace(data_x, data_y)
sample_ws = ScaleX(sample_ws, -1, "Add")  # centre the peak over 0

symm_ws = Symmetrise(InputWorkspace=sample_ws, XMin=0.05, XMax=8.0)