Symmetrise v1

../_images/Symmetrise-v1_dlg.png

Symmetrise dialog.

Summary

Make asymmetric workspace data symmetric.

Properties

Name Direction Type Default Description
InputWorkspace Input MatrixWorkspace Mandatory Sample to run with
SpectraRange Input int 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)

Categories: Algorithms | CorrectionFunctions\SpecialCorrections