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

.. index::
    ! NXcg_tetrahedron (base class)
    ! cg_tetrahedron (base class)
    see: cg_tetrahedron (base class); NXcg_tetrahedron

.. _NXcg_tetrahedron:

================
NXcg_tetrahedron
================

**Status**:

  base class, extends :ref:`NXcg_primitive`

**Description**:

  .. collapse:: Computational geometry description of a set of tetrahedra. ...

      Computational geometry description of a set of tetrahedra.

      Among hexahedral elements, tetrahedral elements are one of the most
      frequently used geometric primitive for meshing and describing volumetric
      objects in continuum-field simulations.

**Symbols**:

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

  **c**: The cardinality of the set, i.e. the number of tetrahedra.

**Groups cited**:
  :ref:`NXcg_face_list_data_structure`, :ref:`NXcg_half_edge_data_structure`

.. index:: NXcg_face_list_data_structure (base class); used in base class, NXcg_half_edge_data_structure (base class); used in base class

**Structure**:

  .. _/NXcg_tetrahedron/face_area-field:

  .. index:: face_area (field)

  **face_area**: (optional) :ref:`NX_NUMBER <NX_NUMBER>` (Rank: 2, Dimensions: [c, 4]) {units=\ :ref:`NX_AREA <NX_AREA>`} 

    Area of each of the four triangular faces of each tetrahedron.

  .. _/NXcg_tetrahedron/edge_length-field:

  .. index:: edge_length (field)

  **edge_length**: (optional) :ref:`NX_NUMBER <NX_NUMBER>` (Rank: 2, Dimensions: [c, 6]) {units=\ :ref:`NX_LENGTH <NX_LENGTH>`} 

    Length of each edge of each tetrahedron.

  .. _/NXcg_tetrahedron/tetrahedra-group:

  **tetrahedra**: (optional) :ref:`NXcg_face_list_data_structure` 

    Combined storage of all primitives of all tetrahedra.

  .. _/NXcg_tetrahedron/tetrahedronID-group:

  **tetrahedron**\ :bolditalic:`ID`: (optional) :ref:`NXcg_face_list_data_structure` 

    Individual storage of each tetrahedron.

  .. _/NXcg_tetrahedron/tetrahedron_half_edgeID-group:

  **tetrahedron_half_edge**\ :bolditalic:`ID`: (optional) :ref:`NXcg_half_edge_data_structure` 

    Individual storage of each tetrahedron as a graph.


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

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


* :ref:`/NXcg_tetrahedron/edge_length-field </NXcg_tetrahedron/edge_length-field>`
* :ref:`/NXcg_tetrahedron/face_area-field </NXcg_tetrahedron/face_area-field>`
* :ref:`/NXcg_tetrahedron/tetrahedra-group </NXcg_tetrahedron/tetrahedra-group>`
* :ref:`/NXcg_tetrahedron/tetrahedron_half_edgeID-group </NXcg_tetrahedron/tetrahedron_half_edgeID-group>`
* :ref:`/NXcg_tetrahedron/tetrahedronID-group </NXcg_tetrahedron/tetrahedronID-group>`

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