LoadNexusProcessed

From MantidProject

Jump to: navigation, search

Contents

Summary

The LoadNexusProcessed algorithm will read the given Nexus Processed data file containing a Mantid Workspace. The data is placed in the named workspace. LoadNexusProcessed may be invoked by LoadNexus if it is given a Nexus file of this type.

Properties

Order Name Direction Type Default Description
1 FileName Input File name Mandatory The name of the Nexus file to read, as a full or relative path.
2 OutputWorkspace Output Workspace Mandatory The name of the workspace to be created as the output of the algorithm. A workspace of this name will be created and stored in the Analysis Data Service. For multiperiod files, one workspace may be generated for each period. Currently only one workspace can be saved at a time so multiperiod Mantid files are not generated.
3 Spectrum_min Input Integer Optional Number of first spectrum to read.
4 Spectrum_max Input Integer Optional Number of last spectrum to read.
5 Spectrum_list Input Integer list Optional List of spectrum numbers to read.
6 EntryNumber Input Integer Optional The particular entry number to read. Default load all workspaces and creates a workspacegroup.

Description

The algorithm LoadNexusProcessed will read a Nexus data file created by SaveNexusProcessed and place the data into the named workspace. The file name can be an absolute or relative path and should have the extension .nxs, .nx5 or .xml. Warning - using XML format can be extremely slow for large data sets and generate very large files. The optional parameters can be used to control which spectra are loaded into the workspace (not yet implemented). If spectrum_min and spectrum_max are given, then only that range to data will be loaded.

A Mantid Nexus file may contain several workspace entries each labelled with an integer starting at 1. By default the highest number workspace is read, earlier ones can be accessed by setting the EntryNumber.

If the saved data has a reference to an XML file defining instrument geometry this will be read.


Time series data

The log data in the Nexus file (NX_LOG sections) is loaded as TimeSeriesProperty data within the workspace. Time is stored as seconds from the Unix epoch. Only floating point logs are stored and loaded at present.

Subalgorithms used

The subalgorithms used by LoadMuonNexus are:

  • LoadInstrument - this algorithm looks for an XML description of the instrument and if found reads it.

Source Code

Header LoadNexusProcessed.h

Source LoadNexusProcessed.cpp

Personal tools
Create a book