/*!
\page medcouplingexamplescpponly MEDCoupling C++ examples

\anchor cpp_mcfielddouble_fillFromAnalytic_c_func
<br><h2> Filling a field using a C function</h2>

We want to create a 3D vector field lying on a 2D mesh using a C function as a value
generator. For that, first, we define the function that computes 3 values basing on 2
coordinates of a 2D point.
\snippet MEDCouplingExamplesTest.cxx Snippet_MEDCouplingFieldDouble_fillFromAnalytic_c_func_0
Then we create the 2D mesh and the field on it, and finally we use
\ref ParaMEDMEM::MEDCouplingFieldDouble::fillFromAnalytic(int nbOfComp, FunctionToEvaluate func) "fillFromAnalytic()"
to fill the field with values each composed of 3 components.
\snippet MEDCouplingExamplesTest.cxx Snippet_MEDCouplingFieldDouble_fillFromAnalytic_c_func_1
As a result, number of tuples in the field equals to the number of cells in the mesh,
and number of components equals to 3 as required.


\anchor cpp_mcfielddouble_applyFunc_c_func
<br><h2> Changing a field by applying a C function</h2>

We want to transform a 2D vector field to a 3D vector field by
applying a C function to each vector value. For that, first, we define the function
that computes 3 values basing on 2 components of a 2D vector.
\snippet MEDCouplingExamplesTest.cxx Snippet_MEDCouplingFieldDouble_fillFromAnalytic_c_func_0
Then we create the 2D mesh and the vector field on it.
\snippet MEDCouplingExamplesTest.cxx Snippet_MEDCouplingFieldDouble_applyFunc_c_func_1
Finally we use
\ref ParaMEDMEM::MEDCouplingFieldDouble::applyFunc(int nbOfComp, FunctionToEvaluate func) "applyFunc()"
to change the field values.
\snippet MEDCouplingExamplesTest.cxx Snippet_MEDCouplingFieldDouble_applyFunc_c_func_2
As a result, number of tuples in the field equals to the number of cells in the mesh,
and number of components becomes equal to 3 as required.


*/