.. auto-generated by script ../../../../utils/nxdl2rst.py from the NXDL source NXgraph_node_set.nxdl.xml

.. index::
    ! NXgraph_node_set (base class)
    ! graph_node_set (base class)
    see: graph_node_set (base class); NXgraph_node_set

.. _NXgraph_node_set:

================
NXgraph_node_set
================

**Status**:

  base class, extends :ref:`NXobject`

**Description**:

  A set of nodes/vertices in space representing members of a graph.

**Symbols**:

  The symbols used in the schema to specify e.g. dimensions of arrays.

  **d**: The dimensionality of the graph. Eventually use one for categorical.

  **c**: The cardinality of the set, i.e. the number of nodes/vertices of the graph.

**Groups cited**:
  none

**Structure**:

  .. _/NXgraph_node_set/dimensionality-field:

  .. index:: dimensionality (field)

  **dimensionality**: (optional) :ref:`NX_POSINT <NX_POSINT>` {units=\ :ref:`NX_UNITLESS <NX_UNITLESS>`}


  .. _/NXgraph_node_set/cardinality-field:

  .. index:: cardinality (field)

  **cardinality**: (optional) :ref:`NX_POSINT <NX_POSINT>` {units=\ :ref:`NX_UNITLESS <NX_UNITLESS>`}


  .. _/NXgraph_node_set/identifier_offset-field:

  .. index:: identifier_offset (field)

  **identifier_offset**: (optional) :ref:`NX_INT <NX_INT>` {units=\ :ref:`NX_UNITLESS <NX_UNITLESS>`}

    Integer which specifies the first index to be used for distinguishing
    nodes. Identifiers are defined either implicitly
    or explicitly. For implicit indexing the identifiers are defined on the
    interval [identifier_offset, identifier_offset+c-1].
    For explicit indexing the identifier array has to be defined.

    The identifier_offset field can for example be used to communicate if the
    identifiers are expected to start from 1 (referred to as Fortran-/Matlab-)
    or from 0 (referred to as C-, Python-style index notation) respectively.

  .. _/NXgraph_node_set/identifier-field:

  .. index:: identifier (field)

  **identifier**: (optional) :ref:`NX_INT <NX_INT>` (Rank: 1, Dimensions: [c]) {units=\ :ref:`NX_UNITLESS <NX_UNITLESS>`}

    Integer used to distinguish nodes for explicit indexing.

  .. _/NXgraph_node_set/is_a-field:

  .. index:: is_a (field)

  **is_a**: (optional) :ref:`NX_CHAR <NX_CHAR>` (Rank: 1, Dimensions: [c])

    A human-readable qualifier which type or e.g. class instance the
    node is an instance of. As e.g. a NeXus application definition is a
    graph, more specifically a hierarchical directed labelled property graph,
    instances which are groups like NXgraph_node_set could have an is_a
    qualifier reading NXgraph_node_set.

  .. _/NXgraph_node_set/label-field:

  .. index:: label (field)

  **label**: (optional) :ref:`NX_CHAR <NX_CHAR>` (Rank: 1, Dimensions: [c])

    A human-readable label/caption/tag of the graph.


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

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


* :ref:`/NXgraph_node_set/cardinality-field </NXgraph_node_set/cardinality-field>`
* :ref:`/NXgraph_node_set/dimensionality-field </NXgraph_node_set/dimensionality-field>`
* :ref:`/NXgraph_node_set/identifier-field </NXgraph_node_set/identifier-field>`
* :ref:`/NXgraph_node_set/identifier_offset-field </NXgraph_node_set/identifier_offset-field>`
* :ref:`/NXgraph_node_set/is_a-field </NXgraph_node_set/is_a-field>`
* :ref:`/NXgraph_node_set/label-field </NXgraph_node_set/label-field>`

**NXDL Source**:
  https://github.com/nexusformat/definitions/blob/main/base_classes/NXgraph_node_set.nxdl.xml