utils: add is_approx function and expose it

CMakeLists.txt

 #
 # Copyright (c) 2014-2019 CNRS
-# Copyright (c) 2018-2019 INRIA
+# Copyright (c) 2018-2020 INRIA
 #
 
 CMAKE_MINIMUM_REQUIRED(VERSION 2.6)
@@ -73,6 +73,7 @@ SEARCH_FOR_BOOST()
 # ----------------------------------------------------
 SET(${PROJECT_NAME}_UTILS_HEADERS
   include/eigenpy/utils/scalar-name.hpp
+  include/eigenpy/utils/is-approx.hpp
   )
 
 SET(${PROJECT_NAME}_SOLVERS_HEADERS

include/eigenpy/utils/is-approx.hpp

+/*
+* Copyright 2020 INRIA
+*/
+
+#ifndef __eigenpy_utils_scalar_is_approx_hpp__
+#define __eigenpy_utils_scalar_is_approx_hpp__
+
+#include <Eigen/Core>
+
+namespace eigenpy
+{
+  template<typename MatrixType1, typename MatrixType2>
+  inline bool is_approx(const Eigen::MatrixBase<MatrixType1> & mat1,
+                        const Eigen::MatrixBase<MatrixType2> & mat2,
+                        const typename MatrixType1::Scalar & prec = Eigen::NumTraits<typename MatrixType1::Scalar>::dummy_precision())
+  {
+    return mat1.isApprox(mat2,prec);
+  }
+}
+
+#endif // ifndef __eigenpy_utils_scalar_is_approx_hpp__

python/main.cpp

@@ -13,10 +13,28 @@
 #include "eigenpy/solvers/preconditioners.hpp"
 #include "eigenpy/decompositions/decompositions.hpp"
 
+#include "eigenpy/utils/is-approx.hpp"
+
 #include <boost/python/scope.hpp>
 
+#define DEFINE_IS_APPROX(MatType) \
+  BOOST_PYTHON_FUNCTION_OVERLOADS(is_approx_overload##MatType,eigenpy::is_approx,2,3)
+
+#define EXPOSE_IS_APPROX(MatType) \
+  bp::def("is_approx", \
+          (bool (*)(const Eigen::MatrixBase<MatType> &, \
+                    const Eigen::MatrixBase<MatType> &, \
+                    const MatType::Scalar &))eigenpy::is_approx<MatType,MatType>, \
+                    is_approx_overload##MatType(bp::args("A","B","prec"), \
+          "Returns True if A is approximately equal to B, within the precision determined by prec."))
+
+
 using namespace eigenpy;
 
+DEFINE_IS_APPROX(MatrixXd)
+DEFINE_IS_APPROX(MatrixXf)
+
+
 BOOST_PYTHON_MODULE(eigenpy)
 {
   namespace bp = boost::python;
@@ -42,5 +60,11 @@ BOOST_PYTHON_MODULE(eigenpy)
     register_symbolic_link_to_registered_type<Eigen::ComputationInfo>();
   }
   
+  {
+    using namespace Eigen;
+    EXPOSE_IS_APPROX(MatrixXd);
+    EXPOSE_IS_APPROX(MatrixXf);
+  }
+  
   exposeDecompositions();
 }