Choosing the post-treatment location
================================


OPERATION = 'EXTRACTION' or 'MOYENNE'
-------------------------------------


Syntax
~~~~~~


.. code-block:: text

    ♦ GROUP_NO = lgrno, [l_gr_node]
◊/TOUT = 'OUI',
/GROUP_MA = lgrma, [l_gr_mesh]


Operands GROUP_NO/TOUT/GROUP_MA
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


* The argument for GROUP_NO is a list of node groups. Nodes are processed in the order provided by the user. To reorder the nodes in a list, use the command DEFI_GROUP/OPTION =' NOEUD_ORDO '[:external:ref:`U4.22.01 <U4.22.01>`]


* The GROUP_MA keyword allows you to limit post-processing to a list of mesh groups.

TOUT = 'OUI' comes back to the standard case (we consider all the meshes). These keywords can only be used with GROUP_NO.

*Notes:*

It is not recommended to use GROUP_MAavec the MOYENNEsauf operation if the elements are segments. Recall that the operation MOYENNEcalcule of quantities following a length L. For more information, refer to the paragraph dedicated to the OPERATIONoù keyword. The quantities calculated using this option are presented.

*The keyword* TOUT =' OUI '*means "all mesh cells" Nodal elements assigned directly to the mesh nodes (* AFFE_MODELE/NOEUD *), which are otherwise not recommended, are ignored from post-processing.*


Notions of post-processing points and examples
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Post-processing points are the points in :math:`\Omega` where components (or derived quantities) are evaluated. The extraction operation performs this evaluation.


Example of post-processing points specified by the GROUP_NO keyword
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


.. image:: images/10000A4C000014AC0000182F9F40293B2295C902.svg
    :width: 266
    :height: 312


.. _RefImage_10000A4C000014AC0000182F9F40293B2295C902.svg:

**Figure 4.3.3-a**

This figure shows a post-processing location built from a list of nodes.

The post-processing points are the nodes represented, the post-processing location is the broken line connecting them in the order provided by the user, which makes it possible to define a curvilinear abscissa. The value extracted on these lines is interpolated linearly between the values recorded on the nodes. Thus, it should be noted that if the post-processing operation is an average calculation, everything happens as if the segment :math:`\mathrm{[}{N}_{\mathrm{47 }}{N}_{61}\mathrm{]}` were entirely contained in :math:`\Omega` **.**

In this case, the curvilinear abscissa is calculated from the path of the nodes, as defined in the node list.

OPERATION = 'EXTREMA' or 'MOYENNE_ARITH'
----------------------------------------


Syntax
~~~~~~


.. code-block:: text
 ♦ | ALL= 'YES',
| GROUP_NO = lgrno, [l_gr_node] | GROUP_MA = lgrma, [l_gr_mesh]


Operands TOUT/GROUP_NO/GROUP_MA
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


* The argument for GROUP_NO is a list of node groups. The knots are not ordered.


* The GROUP_MA keyword allows you to limit post-processing to a list of mesh groups.


* TOUT = 'OUI' comes back to the standard case (we consider all the meshes).