diff --git a/python/src/core/domains/interval/codac_py_IntervalMatrix.cpp b/python/src/core/domains/interval/codac_py_IntervalMatrix.cpp
index 15ea21109..daeec1c5f 100644
--- a/python/src/core/domains/interval/codac_py_IntervalMatrix.cpp
+++ b/python/src/core/domains/interval/codac_py_IntervalMatrix.cpp
@@ -22,6 +22,7 @@
 #include "ibex_Matrix.h"
 #include "codac_Interval.h"
 #include "codac_IntervalMatrix.h"
+#include "codac_matrix_arithmetic.h"
 // Generated file from Doxygen XML (doxygen2docstring.py):
 // todo: #include "codac_py_IntervalMatrix_docs.h"
 
@@ -85,12 +86,12 @@ void export_IntervalMatrix(py::module& m)
 
     // Some sanity checks...
     if(info.format != py::format_descriptor<double>::format())
-        throw std::runtime_error("Incompatible format: expected a double array");
+      throw std::runtime_error("Incompatible format: expected a double array");
 
     if(info.ndim != 2)
-        throw std::runtime_error("Incompatible buffer dimension");
+      throw std::runtime_error("Incompatible buffer dimension");
 
-    ibex::Matrix m((int)info.shape[0], (int)info.shape[1], static_cast<double *>(info.ptr));
+    ibex::Matrix m((int)info.shape[0], (int)info.shape[1], static_cast<double*>(info.ptr));
     return IntervalMatrix(m);
   }))
 
@@ -134,5 +135,8 @@ void export_IntervalMatrix(py::module& m)
   .def( "__mul__", [](IntervalMatrix& m, const Interval& x) { return x*m; })
   .def("shape", [] (IntervalMatrix& o) { return make_tuple(o.nb_rows(), o.nb_cols()); })
   .def("__repr__", [](const IntervalMatrix& x) { ostringstream str; str << x; return str.str(); })
+
+  .def("__or__", [](const IntervalMatrix& x, const IntervalMatrix& y) { return x|y; })
+  .def("__and__", [](const IntervalMatrix& x, const IntervalMatrix& y) { return x&y; })
   ;
 };
\ No newline at end of file
diff --git a/python/src/core/domains/interval/codac_py_IntervalVector.cpp b/python/src/core/domains/interval/codac_py_IntervalVector.cpp
index 28d039d35..01b6ca28e 100644
--- a/python/src/core/domains/interval/codac_py_IntervalVector.cpp
+++ b/python/src/core/domains/interval/codac_py_IntervalVector.cpp
@@ -149,6 +149,28 @@ void export_IntervalVector(py::module& m)
     .def(py::init(&create_from_vector_of_intervals), "list"_a)
     //.def("__init__", &create_from_tuple, "list"_a)
 
+    .def(py::init([](py::array_t<double> b) // create for instance an IntervalVector from a NumPy array
+    {
+      // Request a buffer descriptor from Python
+      py::buffer_info info = b.request();
+
+      // Some sanity checks...
+      if(info.format != py::format_descriptor<double>::format())
+        throw std::runtime_error("Incompatible format: expected a double array");
+
+      if(info.ndim == 1 ||                            // e.g.: a=np.array([1,0,0])
+         (info.ndim == 2 && (int)info.shape[1] == 1)) // e.g.: a=np.array([[1],[0],[0]]) 
+      {
+        ibex::Vector m((int)info.shape[0], static_cast<double*>(info.ptr));
+        return IntervalVector(m);
+      }
+
+      else
+        throw std::runtime_error("Incompatible buffer dimension");
+
+      return IntervalVector(0);
+    }))
+
   // Python vector methods
 
     .def("__len__", &IntervalVector::size)
@@ -310,8 +332,8 @@ void export_IntervalVector(py::module& m)
   // bwd_mul overloading
   //bool (*bwd_mul_1) (const IntervalVector&, Interval&, IntervalVector&) = &ibex::bwd_mul;
   //bool (*bwd_mul_2) (const Interval&, IntervalVector&, IntervalVector&) = &ibex::bwd_mul;
-  m.def( "bwd_mul", (bool (*) (const IntervalVector&, Interval&, IntervalVector&)) &ibex::bwd_mul);
-  m.def( "bwd_mul", (bool (*) (const Interval&, IntervalVector&, IntervalVector&)) &ibex::bwd_mul);
+  m.def("bwd_mul", (bool (*) (const IntervalVector&, Interval&, IntervalVector&)) &ibex::bwd_mul);
+  m.def("bwd_mul", (bool (*) (const Interval&, IntervalVector&, IntervalVector&)) &ibex::bwd_mul);
 
   m.def("max", (IntervalVector(*) (const IntervalVector&, const IntervalVector&)) &max_IntevalVector);
 };
\ No newline at end of file
diff --git a/src/core/CMakeLists.txt b/src/core/CMakeLists.txt
index a7729c813..8ddaba0b0 100644
--- a/src/core/CMakeLists.txt
+++ b/src/core/CMakeLists.txt
@@ -18,6 +18,8 @@
                   ${CMAKE_CURRENT_SOURCE_DIR}/arithmetic/codac_traj_arithmetic.h
                   ${CMAKE_CURRENT_SOURCE_DIR}/arithmetic/codac_traj_arithmetic_scalar.cpp
                   ${CMAKE_CURRENT_SOURCE_DIR}/arithmetic/codac_traj_arithmetic_vector.cpp
+                  ${CMAKE_CURRENT_SOURCE_DIR}/arithmetic/codac_matrix_arithmetic.cpp
+                  ${CMAKE_CURRENT_SOURCE_DIR}/arithmetic/codac_matrix_arithmetic.h
                   ${CMAKE_CURRENT_SOURCE_DIR}/graphics/codac_Figure.h
                   ${CMAKE_CURRENT_SOURCE_DIR}/graphics/codac_Figure.cpp
                   ${CMAKE_CURRENT_SOURCE_DIR}/graphics/vibes/vibes.h
diff --git a/src/core/arithmetic/codac_tube_arithmetic.h b/src/core/arithmetic/codac_tube_arithmetic.h
index 221e9697f..f80abd863 100644
--- a/src/core/arithmetic/codac_tube_arithmetic.h
+++ b/src/core/arithmetic/codac_tube_arithmetic.h
@@ -7,10 +7,7 @@
  *  \copyright  Copyright 2021 Codac Team
  *  \license    This program is distributed under the terms of
  *              the GNU Lesser General Public License (LGPL).
-
-      * \param x
-      * \return Tube output
-      */
+ */
 
 #ifndef __CODAC_TUBE_ARITHMETIC_H__
 #define __CODAC_TUBE_ARITHMETIC_H__