diff --git a/include/core/state_block/state_composite.h b/include/core/state_block/state_composite.h
index 14867387c0d0d579cd3d35370846f201ad1ca4e1..f0bfc5cfe58832605fb36c70c622f2174c974e6c 100644
--- a/include/core/state_block/state_composite.h
+++ b/include/core/state_block/state_composite.h
@@ -29,6 +29,7 @@ class VectorComposite : public std::unordered_map < std::string, Eigen::VectorXd
 {
     public:
         VectorComposite() {};
+        VectorComposite(const StateStructure& _s);
         VectorComposite(const VectorComposite & v) : unordered_map<string, VectorXd>(v){};
         /**
          * \brief Construct from Eigen::VectorXd and structure
diff --git a/src/state_block/state_composite.cpp b/src/state_block/state_composite.cpp
index d0618799c899fb294cddc60eb4b8671e7345a72f..673458e340d8efc1fbdbe494ea8ba50b75bbc427 100644
--- a/src/state_block/state_composite.cpp
+++ b/src/state_block/state_composite.cpp
@@ -24,6 +24,17 @@ VectorComposite::VectorComposite(const VectorXd& _v, const StateStructure& _stru
     }
 }
 
+VectorComposite::VectorComposite (const StateStructure& _s)
+{
+    for (const auto& ckey : _s)
+    {
+        const auto& key = string(1,ckey); // ckey is char
+        this->emplace(key,VectorXd(0));
+    }
+}
+
+
+
 unsigned int VectorComposite::size(const StateStructure &_structure) const
 {
     unsigned int size = 0;