LoadNMoldyn4Ascii1D v1

Summary

Imports 1D dos and vac functions from an nMolDyn 4 output file, convoluting it with a resolution function if required.

Properties

Name	Direction	Type	Default	Description
Directory	Input	string	Mandatory	Path to directory containing dat files
Functions	Input	str list		Names of functions to attempt to load from file
ResolutionConvolution	Input	string	No	Use resolution function to ‘smear’ dos data? Allowed values: [‘No’, ‘TOSCA’]
OutputWorkspace	Output	Workspace	Mandatory	Output workspace name

Description

Loads density of states and velocity autocorrelation data from version 4 of nMOLDYN saved in an ASCII format after being extracted from the ‘.tar’ archive. Will convolute this data with an instrument resolution function if required. Only a TOSCA resolution function is available at present. See below for an example of resolution convolution.

Functions must be provided in the format of the filenames. For example, a function ‘dos_total’ will be loaded if ‘dos_total’ is entered as a chosen function.

Assumptions on data format

The ‘Directory’ property must be given the directory that is produced when you extract the ‘.tar’ archive from nMOLDYN without modifications which must only contain the data files produced from a single nMOLDYN export operation. Crucially, there must be a ‘\frequency.dat’ file in order to load dos data and a ‘\time.dat’ file in order to load vacf data.

Axis Unit Conversions

When loading certain axes from nMOLDYN 4 the units may be converted to an equivalent unit in Mantid. The possible conversions are shown in the table below:

nMOLDYN		Mantid
name	unit	name	unit
frequency	THz	Wavenumber	cm^-1
Time	pSecond	TOF	uSecond

Usage

Example - Loading a simulation from an nMOLDYN 4 data file, without resolution convolution

data = LoadNMoldyn4Ascii1D(Directory=r'C:\MantidInstall\data\pristinedata',
                           Functions=['dos_total', 'vacf_total'])

for ws in data:
    print(ws.name())

Output:

data(dos_total)
data(vacf_total)

Categories: AlgorithmIndex | Simulation | Inelastic\DataHandling

Source

Python: LoadNMoldyn4Ascii1D.py