diff --git a/python/py_solver.cc b/python/py_solver.cc
index 7ac4674e2..a0146642d 100644
--- a/python/py_solver.cc
+++ b/python/py_solver.cc
@@ -1,47 +1,53 @@
 /* -------------------------------------------------------------------------- */
 #include "py_solver.hh"
 #include "py_aka_array.hh"
 /* -------------------------------------------------------------------------- */
 #include <model.hh>
 #include <non_linear_solver.hh>
 #include <sparse_matrix_aij.hh>
 /* -------------------------------------------------------------------------- */
 #include <pybind11/operators.h>
 #include <pybind11/pybind11.h>
 #include <pybind11/stl.h>
 /* -------------------------------------------------------------------------- */
 namespace py = pybind11;
 /* -------------------------------------------------------------------------- */
 
 namespace akantu {
 
 /* -------------------------------------------------------------------------- */
 void register_solvers(py::module & mod) {
   py::class_<SparseMatrix>(mod, "SparseMatrix")
       .def("getMatrixType", &SparseMatrix::getMatrixType)
       .def("size", &SparseMatrix::size)
       .def("zero", &SparseMatrix::zero)
       .def("saveProfile", &SparseMatrix::saveProfile)
       .def("saveMatrix", &SparseMatrix::saveMatrix)
       .def(
           "add", [](SparseMatrix & self, UInt i, UInt j) { self.add(i, j); },
           "Add entry in the profile")
       .def(
           "add",
           [](SparseMatrix & self, UInt i, UInt j, Real value) {
             self.add(i, j, value);
           },
           "Add the value to the matrix")
+      .def(
+          "add",
+          [](SparseMatrix & self, SparseMatrix & A, Real alpha) {
+            self.add(A, alpha);
+          },
+          "Add a matrix to the matrix", py::arg("A"), py::arg("alpha") = 1.)
       .def("__call__", [](const SparseMatrix & self, UInt i, UInt j) {
         return self(i, j);
       });
 
   py::class_<SparseMatrixAIJ, SparseMatrix>(mod, "SparseMatrixAIJ")
       .def("getIRN", &SparseMatrixAIJ::getIRN)
       .def("getJCN", &SparseMatrixAIJ::getJCN)
       .def("getA", &SparseMatrixAIJ::getA);
 
   py::class_<SolverVector>(mod, "SolverVector");
 }
 
 } // namespace akantu