%feature("docstring") OT::P1LagrangeEvaluation
"Data based math evaluation implementation.

Available constructors:

    P1LagrangeEvaluation(*field*)

Parameters
----------
field : :class:`~openturns.Field`
    Field :math:`\cF` defining the parameters of a P1 Lagrange interpolation function.

See also
--------
Function, AggregatedEvaluation, DualLinearCombinationEvaluation,
LinearFunction

Notes
-----
It returns a :class:`~openturns.Function` that implements the P1 Lagrange interpolation function :math:`f : \cD_N \rightarrow \Rset^p` :

.. math::
    \forall \vect{x} \in \Rset^n, f(\vect{x}) = \sum_{\vect{\xi}_i\in\cV(\vect{x})}\alpha_i f(\vect{\xi}_i)

where :math:`\cD_N` is a :class:`~openturns.Mesh`, :math:`\cV(\vect{x})` is the simplex in :math:`\cD_N` that contains :math:`\vect{x}`, :math:`\alpha_i` are the barycentric coordinates of :math:`\vect{x}` wrt the vertices :math:`\vect{\xi}_i` of :math:`\cV(\vect{x})`:

.. math::
    \vect{x}=\sum_{\vect{\xi}_i\in\cV(\vect{x})}\alpha_i\vect{\xi}_i

Examples
--------
Create a P1 Lagrange evaluation:

>>> import openturns as ot
>>> field = ot.Field(ot.RegularGrid(0.0, 1.0, 4), [[0.5], [1.5], [1.0], [-0.5]])
>>> evaluation = ot.P1LagrangeEvaluation(field)
>>> print(evaluation([2.3]))
[0.55]"
// ---------------------------------------------------------------------

%feature("docstring") OT::P1LagrangeEvaluation::getField
"Accessor to the field defining the functions.

Returns
-------
field : :class:`~openturns.Field`
    The field defining the function."

// ---------------------------------------------------------------------

%feature("docstring") OT::P1LagrangeEvaluation::setField
"Accessor to the field defining the functions.

Parameters
----------
field : :class:`~openturns.Field`
    The field defining the function."
