write doc about :

- parameters
- petsc vectors
- petsc matrix
Write documentation on python x feel++ modules #151
[ci skip]

docs/user/modules/python/nav.adoc

@@ -9,3 +9,6 @@
 *** xref:pyfeelpptoolboxes/electric.adoc[Electrostatic]
 *** xref:pyfeelpptoolboxes/fluid.adoc[Fluid Mechanics]
 *** xref:pyfeelpptoolboxes/solid.adoc[Solid Mechanics]
+** xref:pyfeelppmor/index.adoc[{pyfeelppmor}]
+*** xref:pyfeelppmor/parameters.adoc[Parameters]
+*** xref:pyfeelppmor/petscDouble.adoc[PETSc vector and matrix]

docs/user/modules/python/pages/pyfeelppmor/index.adoc

@@ -0,0 +1,5 @@
+= {feelpp} model order reduction in Python
+include::{partialsdir}/header-macros.adoc[]
+
+This sections present the modules developped and the function implemented to handle {fpp} MOR objects in Python. The script link:https://github.com/feelpp/feelpp/blob/develop/mor/pyfeelpp-mor/feelpp/mor/toolboxmor.py[toolboxmor.py] presents the main features, on the case opus-heat.
+

docs/user/modules/python/pages/pyfeelppmor/parameters.adoc

@@ -0,0 +1,33 @@
+= Parameters
+
+Class `ParameterSpaceElement` (more precisely `feelpp.mor._mor.ParameterSpaceElement`). Contains the parameters of the problem.
+
+.Get a parameter from the model
+[source,python]
+----
+Dmu = model.parameterSpace()
+mu = Dmu.element(True, False)
+----
+
+
+== Methods
+
+* `__call__(i: int)` -> `float` : return the _i_-th parameter
+
+* `__str__()` :
+
+[source,python]
+----
+>>> print("mu =", mu)
+mu = [4.37e+00,2.92e+00,1.17e+00,8.75e+05,5.28e+05,2.83e+01]
+----
+
+* `parameterName(i: int)` -> `str` : return the named of the _i_-th parameter
+
+* `parameterNamed(name: str)` -> `float` : return the parameter named `str`
+
+* `setParameter(i: int, value: float)` : set the _i_-th to `value`
+
+* `setParameterNamed(name: str, value: float)` : set the parameter `name` to `value`
+
+* `size()` -> `int` : return the size of the parameter

docs/user/modules/python/pages/pyfeelppmor/petscDouble.adoc

@@ -0,0 +1,38 @@
+== Vector PETSc Double
+
+Class `VectorPetscDouble` (`feelpp._alg.VectorPetscDouble`)
+
+
+=== Methods
+
+* `__init__(*args, **kwargs)` : Overloaded function.
+
+    1. `__init__()`. The vector created is empty.
+    2. `__init__(arg0: int, arg1: feelpp._core.WorldComm)`. The vector created has a size `arg0`.
+    3. `__init__(arg0: int, arg1: int, arg2: feelpp._core.WorldComm)`. The vector created has a global size `arg0`, and a local size `arg1`.
+    4. `__init__(arg0: feelpp._alg.DataMap, arg1: bool)`
+* `clear()` : clear PETSc vector
+* `size()` -> `int` : return  PETSc Vector size
+* `vec()` -> `vec` : return a PETSc Vector that can be manipulated with funciton of the module https://pypi.org/project/petsc4py/[petsc4py]. The functions of this class can be found on the https://www.mcs.anl.gov/petsc/petsc4py-current/docs/apiref/petsc4py.PETSc.Vec-class.html[documentation of PETSc4py].
+* `zero()` : zero PETSc vector
+
+
+== Matrix PETSc Double
+
+Class `MatrixPetscDouble` (`feelpp._alg.MatrixPetscDouble`). The methods of this class are similar to the previous class, the apply on matrices insted of vectors.
+
+
+=== Methods
+
+* `__init__(*args, **kwargs)` : Overloaded function.
+    1. `__init__(arg0: feelpp._core.WorldComm)`
+    2. `__init__(arg0: feelpp._alg.DataMap, arg1: feelpp._alg.DataMap)`
+    3. `__init__(arg1: feelpp._alg.DataMap, arg2: feelpp._core.WorldComm)`
+* `clear()` : clear PETSc matrix
+* `mat(...)` -> `mat` : return a PETSc sparse matrix. See https://www.mcs.anl.gov/petsc/petsc4py-current/docs/apiref/petsc4py.PETSc.Mat-class.html[the documentation].
+* `rowStart()` -> `int` : return PETSc Matrix row start. This method is usefull is the matrix is shared with many processors, as the following.
+* `rowStop()` -> `int` : return  PETSc Matrix row stop
+* `size1()` -> `int` : return  PETSc Matrix row size
+* `size2()` -> `int` : return  PETSc Matrix column size
+* `shape()` -> `Tuple[int,int]` : return PETSc Matrix shape (`(row size, column size)`)
+* `zero()` : zero PETSc matrix