.. _connectivity_page:

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Nodal connectivity of elements
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The following images show order of nodes in correctly defined elements.

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| Edge (segment): linear and quadratic                                         |
|     .. image:: ../images/connectivity_edge.png                               |
|		:align: center                                                 |
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| Triangle: linear, quadratic and bi-quadratic                                 |
|     .. image:: ../images/connectivity_tria.png                               |
|		:align: center                                                 |
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| Quadrangle: linear, quadratic and bi-quadratic                               |
|     .. image:: ../images/connectivity_quad.png                               |
|		:align: center                                                 |
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| Polygon: linear and quadratic                                                |
|     .. image:: ../images/connectivity_polygon.png                            |
|		:align: center                                                 |
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| Tetrahedron: linear and quadratic                                            |
|     .. image:: ../images/connectivity_tetra.png                              |
|		:align: center                                                 |
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| Hexahedron: linear, quadratic and tri-quadratic                              |
|	.. image:: ../images/connectivity_hexa.png                             |
|		:align: center                                                 |
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| Pentahedron: linear and quadratic                                            |
|	.. image:: ../images/connectivity_penta.png                            |
|		:align: center                                                 |
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| Pyramid: linear and quadratic                                                |
|	.. image:: ../images/connectivity_pyramid.png                          |
|		:align: center                                                 |
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| Hexagonal prism                                                              |
|	.. image:: ../images/connectivity_hex_prism.png                        |
|		:align: center                                                 |
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| Polyhedron is defined by                                                     |
|	* a sequence of nodes defining all facets                              |
|	* a sequence of number of nodes per facet                              |
|                                                                              |
|      **Nodes**:                                                              |
|      Node1_of_Facet1, Node2_of_Facet1, ..., NodeN_of_Facet1,                 |
|      Node1_of_Facet2, Node2_of_Facet2, ..., NodeN_of_Facet2,                 |
|      Node1_of_FacetM, Node2_of_FacetM, ..., NodeN_of_FacetM                  |
|                                                                              |
|      **Quantity** of nodes per facet:                                        |
|      NbNodes_in_Facet1, NbNodes_in_Facet2, ..., NbNodes_in_FacetM            |
|                                                                              |
|      For example the polyhedron shown in the image below is defined by nodes |
|      [ 1,2,3, 1,4,5,2, 2,5,6,3, 3,6,4,1, 4,7,9,5, 5,9,8,6, 6,8,7,4, 7,8,9 ]  |
|      and quantities [ 3, 4, 4, 4, 4, 4, 4, 3 ]                               |
|                                                                              |
|	.. image:: ../images/connectivity_polyhedron.png                       |
|		:align: center                                                 |
|                                                                              |
|      Order of nodes of a facet must assure outward direction of its normal.  |
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