Pyfeelpp: Methods to read and change parameters from json model files

[Trophime]

Unless I'm wrong, there is no way to interact with the parameters defined in a json model file from the python interface.
(at least in the develop or the prudhomm-issue1626 branch). We definitively need this kind of features.

[romainhild]

It depends on which toolbox. For the heat toolbox for example, you can do the following

heat.addParameterInModelProperties("name", value)
heat.updateParameterValues()

But in other toolboxes, for example cfpdes, the method updateParameterValues() has not been wrapped in python.

To read the parameters, we need to wrap the ModelProperties and ModelParameters class.

[romainhild]

I provided the changes that you need on slack.

[Trophime]

I apply the following patch:

--- a/toolboxes/pyfeelpp-toolboxes/feelpp/toolboxes/coefficientformpdes/cfpdes.cpp
+++ b/toolboxes/pyfeelpp-toolboxes/feelpp/toolboxes/coefficientformpdes/cfpdes.cpp
@@ -68,9 +68,13 @@ void defSM(py::module &m)
         .def( "exportResults", static_cast<void ( toolbox_t::* )()>( &toolbox_t::exportResults ), "export the results of the cfpde problem" )
         .def( "checkResults", static_cast<bool ( toolbox_t::* )() const>( &toolbox_t::checkResults ), "check the results of the cfpde problem" )
         //        .def("exportResults",static_cast<void (toolbox_t::*)( double )>(&toolbox_t::exportResults), "export the results of the heat mechanics problem", py::arg("time"))
+
+
+        .def( "setMesh", &toolbox_t::setMesh, "set the mesh", py::arg( "mesh" ) )
+        .def( "updateParameterValues", &toolbox_t::updateParameterValues, "update parameter values" )
         ;
 }
-    
+
 
 PYBIND11_MODULE(_cfpdes, m )
 {

Now I got an error with calling updateParameterValues:

Thread 1 "python3" received signal SIGSEGV, Segmentation fault.
0x00007f6a6ce354cd in ?? () from /usr/local/lib/libfeelpp_toolbox_coefficientformpdes_2dG1.so.1.0

I certainly miss something, but dunno what to do

[Trophime]

Trying with heat.py does not work either:

python3 heat.py 
Welcome to the Feel++ Toolboxes
[ Starting Feel++ ] application heat.py version 0.1 date 2021-Jul-08
 . heat.py files are stored in /home/feelpp/feelppdb/./np_1
 .. logfiles :/home/feelpp/feelppdb/./np_1/logs
Reading /home/feelpp/heat2dCase2.cfg...
heat(2,1)
[modelProperties] Loading Model Properties : "/home/feelpp/heat2dCase2.json"
{{T0_bottom,20},{T0_top,0},{h_bottom,9.09091},{h_top,16.6667},}
*** Aborted at 1625736845 (unix time) try "date -d @1625736845" if you are using GNU date ***
PC: @                0x0 (unknown)
*** SIGSEGV (@0x88) received by PID 1213 (TID 0x7f73767b2740) from PID 136; stack trace: ***
    @     0x7f73769c4210 (unknown)
    @     0x7f7351e6a45d (unknown)
    @     0x7f7351e5033b Feel::FeelModels::Heat<>::updateParameterValues()
    @     0x7f7360077bfb (unknown)
    @     0x7f7360059bc1 (unknown)
    @           0x5f2cc9 PyCFunction_Call
    @           0x5f3010 _PyObject_MakeTpCall
    @           0x50bf55 (unknown)
    @           0x56fb87 _PyEval_EvalFrameDefault
    @           0x568d9a _PyEval_EvalCodeWithName
    @           0x68cdc7 PyEval_EvalCode
    @           0x67e161 (unknown)
    @           0x67e1df (unknown)
    @           0x67e281 (unknown)
    @           0x67e627 PyRun_SimpleFileExFlags
    @           0x6b6e62 Py_RunMain
    @           0x6b71ed Py_BytesMain
    @     0x7f73769a50b3 __libc_start_main
    @           0x5f96de _start
    @                0x0 (unknown)
Segmentation fault (core dumped)

[Trophime]

In fact it works provided you call updateParametersValues after init method ;)

[Trophime]

The proper way to change parameters is to use what @romainhild did: for instance with cfpdes

f=cfpdes.cfpdes(dim=2)
f.init()

f.addParameterInModelProperties("T0_top", 10)
f.updateParameterValues()