\(\renewcommand\AA{\unicode{x212B}}\)

Symmetrise v1

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: AlgorithmIndex | CorrectionFunctions\SpecialCorrections

Source

Python: Symmetrise.py