base class, extends NXobject
(required) NXentry describes the measurement.
The top-level NeXus group which contains all the data and associated information that comprise a single measurement. It is mandatory that there is at least one group of this type in the NeXus file.
No symbol table
- Groups cited:
@default: (optional) NX_CHAR
Declares which NXdata (or NXsubentry) group contains the data to be shown by default. It is needed to resolve ambiguity when more than one NXdata group exists. The value is the name of the default NXdata group.
It is recommended (as of NIAC2014 1) to use this attribute to help define the path to the default dataset to be plotted.
NIAC2014 discussion summary: https://www.nexusformat.org/2014_How_to_find_default_data.html
@IDF_Version: (optional) NX_CHAR
ISIS Muon IDF_Version
title: (optional) NX_CHAR
Extended title for entry
experiment_identifier: (optional) NX_CHAR
Unique identifier for the experiment, defined by the facility, possibly linked to the proposals
experiment_description: (optional) NX_CHAR
Brief summary of the experiment, including key objectives.
collection_identifier: (optional) NX_CHAR
User or Data Acquisition defined group of NeXus files or NXentry
collection_description: (optional) NX_CHAR
Brief summary of the collection, including grouping criteria.
entry_identifier: (optional) NX_CHAR
unique identifier for the measurement, defined by the facility.
entry_identifier_uuid: (optional) NX_CHAR
UUID identifier for the measurement.
@version: (optional) NX_CHAR
Version of UUID used
features: (optional) NX_CHAR
Reserved for future use by NIAC.
definition: (optional) NX_CHAR
(alternate use: see same field in NXsubentry for preferred)
Official NeXus NXDL schema to which this entry conforms.
This field is provided so that NXentry can be the overlay position in a NeXus data file for an application definition and its set of groups, fields, and attributes.
It is advised to use NXsubentry, instead, as the overlay position.
@version: (optional) NX_CHAR
NXDL version number
@URL: (optional) NX_CHAR
URL of NXDL file
definition_local: (optional) NX_CHAR
start_time: (optional) NX_DATE_TIME
Starting time of measurement
end_time: (optional) NX_DATE_TIME
Ending time of measurement
Duration of measurement
Time transpired actually collecting data i.e. taking out time when collection was suspended due to e.g. temperature out of range
run_cycle: (optional) NX_CHAR
Such as “2007-3”. Some user facilities organize their beam time into run cycles.
program_name: (optional) NX_CHAR
revision: (optional) NX_CHAR
Revision id of the file due to re-calibration, reprocessing, new analysis, new instrument definition format, …
@comment: (optional) NX_CHAR
This is the flightpath before the sample position. This can be determined by a chopper, by the moderator or the source itself. In other words: it the distance to the component which gives the T0 signal to the detector electronics. If another component in the NXinstrument hierarchy provides this information, this should be a link.
DATA: (optional) NXdata
The data group
Before the NIAC2016 meeting 2, at least one NXdata group was required in each NXentry group. At the NIAC2016 meeting, it was decided to make NXdata an optional group in NXentry groups for data files that do not use an application definition. It is recommended strongly that all NeXus data files provide a NXdata group. It is permissable to omit the NXdata group only when defining the default plot is not practical or possible from the available data.
For example, neutron event data may not have anything that makes a useful plot without extensive processing.
Certain application definitions override this decision and require an NXdata group in the NXentry group. The
minOccurs=0attribute in the application definition will indicate the NXdata group is optional, otherwise, it is required.
experiment_documentation: (optional) NXnote
Description of the full experiment (document in pdf, latex, …)
notes: (optional) NXnote
Notes describing entry
thumbnail: (optional) NXnote
A small image that is representative of the entry. An example of this is a 640x480 jpeg image automatically produced by a low resolution plot of the NXdata.
@type: (optional) NX_CHAR
The mime type should be an
USER: (optional) NXuser
SAMPLE: (optional) NXsample
INSTRUMENT: (optional) NXinstrument
COLLECTION: (optional) NXcollection
MONITOR: (optional) NXmonitor
PARAMETERS: (optional) NXparameters
PROCESS: (optional) NXprocess
SUBENTRY: (optional) NXsubentry
Table of hypertext anchors for all groups, fields, attributes, and links defined in this class.
documentation (reST source) anchor
web page (HTML) anchor