[Minor] Address PR comment

bindings/python/multibody/expose-liegroups.cpp

@@ -4,6 +4,7 @@
 
 #include "pinocchio/bindings/python/fwd.hpp"
 #include "pinocchio/bindings/python/multibody/liegroups.hpp"
+#include "pinocchio/bindings/python/utils/namespace.hpp"
 
 #include <eigenpy/memory.hpp>
 
@@ -36,17 +37,9 @@ void exposeLieGroups()
     CartesianProductOperationVariantTpl<double,0,LieGroupCollectionDefaultTpl>
     >::expose("LieGroup");
 
-  bp::scope current;
-  std::string submoduleName(bp::extract<const char*>(current.attr("__name__")));
-  submoduleName.append(".liegroups");
-
-  // Create the submodule, and attach it to the current scope.
-  bp::object submodule(bp::borrowed(PyImport_AddModule(submoduleName.c_str())));
-  current.attr("liegroups") = submodule;
-
   {
     // Switch the scope to the submodule, add methods and classes.
-    bp::scope submoduleScope = submodule;
+    bp::scope submoduleScope = getOrCreatePythonNamespace("liegroups");
 
     bp::def("R1", makeLieGroup<VectorSpaceOperationTpl<1,double,0> >);
     bp::def("R2", makeLieGroup<VectorSpaceOperationTpl<2,double,0> >);

src/multibody/liegroup/cartesian-product-variant.hpp

@@ -53,7 +53,7 @@ namespace pinocchio
     ///
     /// \param[in] lg Lie group variant to insert inside the Cartesian product
     ///
-    CartesianProductOperationVariantTpl(const LieGroupGeneric & lg)
+    explicit CartesianProductOperationVariantTpl(const LieGroupGeneric & lg)
     : m_nq(0), m_nv(0)
     , lg_nqs(0), lg_nvs(0)
     , m_neutral(0)

src/multibody/liegroup/liegroup-variant-visitors.hxx

@@ -452,7 +452,7 @@ namespace pinocchio
                      const ArgumentPosition arg,
                      const AssignmentOperatorType op)
     {
-      assert((arg==ARG0||arg==ARG1) && "arg should be either ARG0 or ARG1");
+      PINOCCHIO_CHECK_INPUT_ARGUMENT(arg==ARG0||arg==ARG1, "arg should be either ARG0 or ARG1");
       switch (arg) {
         case ARG0:
           if(dIntegrateOnTheLeft) lg.dIntegrate_dq(q, v, SELF, J_in, J_out, op);

unittest/python/bindings_liegroups.py

 import unittest
 import pinocchio as pin
 import numpy as np
-from pinocchio.utils import eye,zero,rand
-
-ones = lambda n: np.ones([n, 1] if isinstance(n, int) else n)
 
 class TestLiegroupBindings(unittest.TestCase):