diff --git a/src/python/bindings_docstring_keyed.cpp b/src/python/bindings_docstring_keyed.cpp
index 4c6bf47e3613005b27a1ae9dc9e8eba006539cb5..c374b2154a4dd6a5761cc4304a39d7123b49fc9c 100644
--- a/src/python/bindings_docstring_keyed.cpp
+++ b/src/python/bindings_docstring_keyed.cpp
@@ -37,6 +37,7 @@ void sisso::register_all()
 
     def("phi_selected_from_file", &str2node::phi_selected_from_file_py);
     def("initialize_values_arr", &node_value_arrs::initialize_values_arr);
+    def("initialize_d_matrix_arr", &node_value_arrs::initialize_d_matrix_arr);
 }
 
 void sisso::feature_creation::registerFeatureSpace()
diff --git a/src/python/feature_creation/FeatureSpace.cpp b/src/python/feature_creation/FeatureSpace.cpp
index c7c24388704413f5dfdbbc88874442fc13c55b2a..cb181dd733d1b6352ae7efe3c6362ada5623a2f0 100644
--- a/src/python/feature_creation/FeatureSpace.cpp
+++ b/src/python/feature_creation/FeatureSpace.cpp
@@ -152,7 +152,7 @@ py::list FeatureSpace::phi_py()
 {
     py::list feat_lst;
     for(auto& feat : _phi)
-        feat_lst.append<ModelNode>(ModelNode(feat->d_mat_ind(), feat->rung(), feat->expr(), feat->postfix_expr(), feat->value(), feat->test_value(), feat->unit()));
+        feat_lst.append<ModelNode>(ModelNode(feat->feat_ind(), feat->rung(), feat->expr(), feat->postfix_expr(), feat->value(), feat->test_value(), feat->unit()));
     return feat_lst;
 }
 
@@ -160,6 +160,6 @@ py::list FeatureSpace::phi_selected_py()
 {
     py::list feat_lst;
     for(auto& feat : _phi_selected)
-        feat_lst.append<ModelNode>(ModelNode(feat->d_mat_ind(), feat->rung(), feat->expr(), feat->postfix_expr(), feat->value(), feat->test_value(), feat->unit()));
+        feat_lst.append<ModelNode>(ModelNode(feat->feat_ind(), feat->rung(), feat->expr(), feat->postfix_expr(), feat->value(), feat->test_value(), feat->unit()));
     return feat_lst;
 }