.. auto-generated by dev_tools.docs.nxdl from the NXDL source base_classes/NXhistory.nxdl.xml -- DO NOT EDIT

.. index::
    ! NXhistory (base class)
    ! history (base class)
    see: history (base class); NXhistory

.. _NXhistory:

=========
NXhistory
=========

**Status**:

  base class, extends :ref:`NXobject`

**Description**:

  .. collapse:: A set of activities that occurred to a physical entity prior/during experiment. ...

      A set of activities that occurred to a physical entity prior/during experiment.

      Ideally, a full report of the previous operations (or links to a chain of operations).
      Alternatively, notes allow for additional descriptors in any format.

**Symbols**:

  No symbol table

**Groups cited**:
  :ref:`NXactivity`, :ref:`NXnote`

.. index:: NXactivity (base class); used in base class, NXnote (base class); used in base class

**Structure**:

  .. _/NXhistory/identifierNAME-field:

  .. index:: identifierNAME (field)

  **identifier**\ :bolditalic:`NAME`: (optional) :ref:`NX_CHAR <NX_CHAR>` :ref:`⤆ </NXobject/identifierNAME-field>`

    .. collapse:: An ID or reference to the location or a unique (globally ...

        An ID or reference to the location or a unique (globally
        persistent) identifier of e.g. another file which gives
        as many as possible details of the history event.

  .. _/NXhistory/ACTIVITY-group:

  :bolditalic:`ACTIVITY`: (optional) :ref:`NXactivity` 

    .. collapse:: Any activity that was performed on the physical entity prior or during the ...

        Any activity that was performed on the physical entity prior or during the
        experiment.

  .. _/NXhistory/NOTE-group:

  :bolditalic:`NOTE`: (optional) :ref:`NXnote` :ref:`⤆ </NXobject/NOTE-group>`

    .. collapse:: A descriptor to keep track of the treatment of the physical entity before or d ...

        A descriptor to keep track of the treatment of the physical entity before or during the
        experiment (NXnote allows to add pictures, audio, movies). Alternatively, a
        reference to the location or a unique identifier or other metadata file. In the
        case these are not available, free-text description.
        This should only be used in case that there is no rigorous description
        using the base classes above. This group can also be used to pull in any activities
        that are not well described by an existing base class definition.

        Any number of instances of NXnote are allowed for describing extra details of
        this activity.


Hypertext Anchors
-----------------

List of hypertext anchors for all groups, fields,
attributes, and links defined in this class.


* :ref:`/NXhistory/ACTIVITY-group </NXhistory/ACTIVITY-group>`
* :ref:`/NXhistory/identifierNAME-field </NXhistory/identifierNAME-field>`
* :ref:`/NXhistory/NOTE-group </NXhistory/NOTE-group>`

**NXDL Source**:
  https://github.com/FAIRmat-NFDI/nexus_definitions/tree/fairmat/base_classes/NXhistory.nxdl.xml