diff --git a/src/opt/mpi/include/rop_types.cc.h b/src/opt/mpi/include/rop_types.cc.h
index 350fba4..813a062 100644
--- a/src/opt/mpi/include/rop_types.cc.h
+++ b/src/opt/mpi/include/rop_types.cc.h
@@ -3,85 +3,89 @@
 
 namespace CNORXZ
 {
-    /*================+
-     |    CROpRoot    |
-     +================*/
+    namespace mpi
+    {
+
+	/*================+
+	 |    CROpRoot    |
+	 +================*/
     
-    template <typename T, class IndexT>
-    template <class PosT>
-    constexpr decltype(auto) CROpRoot<T,IndexT>::operator()(const PosT& pos) const
-    {
-	const SizeT L = mIndex->lmax().val();
-	const SizeT m = mIndex->myrank()
-	const SizeT dst = ( m + pos.val() ) % L;
-	const SizeT src = ( m - pos.val() + L ) % L;
-	
-    }
+	template <typename T, class IndexT>
+	template <class PosT>
+	constexpr decltype(auto) CROpRoot<T,IndexT>::operator()(const PosT& pos) const
+	{
+	    const SizeT L = mIndex->lmax().val();
+	    const SizeT m = mIndex->myrank();
+	    const SizeT dst = ( m + pos.val() ) % L;
+	    const SizeT src = ( m - pos.val() + L ) % L;
+	    
+	}
 
-    template <typename T, class IndexT>
-    constexpr decltype(auto) CROpRoot<T,IndexT>::operator()() const
-    {
+	template <typename T, class IndexT>
+	constexpr decltype(auto) CROpRoot<T,IndexT>::operator()() const
+	{
 
-    }
+	}
 
-    template <typename T, class IndexT>
-    template <SizeT I>
-    constexpr decltype(auto) CROpRoot<T,IndexT>::rootSteps(const IndexId<I>& id) const
-    {
+	template <typename T, class IndexT>
+	template <SizeT I>
+	constexpr decltype(auto) CROpRoot<T,IndexT>::rootSteps(const IndexId<I>& id) const
+	{
 
-    }
+	}
     
-    /*===============+
-     |    ROpRoot    |
-     +===============*/
+	/*===============+
+	 |    ROpRoot    |
+	 +===============*/
 
-    template <typename T, class IndexT>
-    template <class PosT>
-    constexpr decltype(auto) ROpRoot<T,IndexT>::operator()(const PosT& pos) const
-    {
+	template <typename T, class IndexT>
+	template <class PosT>
+	constexpr decltype(auto) ROpRoot<T,IndexT>::operator()(const PosT& pos) const
+	{
 
-    }
+	}
 
-    template <typename T, class IndexT>
-    constexpr decltype(auto) ROpRoot<T,IndexT>::operator()() const
-    {
+	template <typename T, class IndexT>
+	constexpr decltype(auto) ROpRoot<T,IndexT>::operator()() const
+	{
 
-    }
+	}
 
-    template <typename T, class IndexT>
-    template <SizeT I>
-    constexpr decltype(auto) ROpRoot<T,IndexT>::rootSteps(const IndexId<I>& id) const
-    {
+	template <typename T, class IndexT>
+	template <SizeT I>
+	constexpr decltype(auto) ROpRoot<T,IndexT>::rootSteps(const IndexId<I>& id) const
+	{
 
-    }
+	}
     
-    /*====================+
-     |    RContraction    |
-     +====================*/
+	/*====================+
+	 |    RContraction    |
+	 +====================*/
 
-    template <class CXpr>
-    constexpr RContraction<CXpr>::RContraction(CXpr&& cxpr) :
-	mCXpr(std::forward<CXpr>(cxpr))
-    {}
+	template <class CXpr>
+	constexpr RContraction<CXpr>::RContraction(CXpr&& cxpr) :
+	    mCXpr(std::forward<CXpr>(cxpr))
+	{}
 
-    template <class CXpr>
-    template <class PosT>
-    constexpr decltype(auto) RContraction<CXpr>::operator()(const PosT& pos) const
-    {
+	template <class CXpr>
+	template <class PosT>
+	constexpr decltype(auto) RContraction<CXpr>::operator()(const PosT& pos) const
+	{
 
-    }
+	}
 
-    template <class CXpr>
-    constexpr decltype(auto) RContraction<CXpr>::operator()() const
-    {
+	template <class CXpr>
+	constexpr decltype(auto) RContraction<CXpr>::operator()() const
+	{
 
-    }
+	}
 
-    template <class CXpr>
-    template <SizeT I>
-    constexpr decltype(auto) RContraction<CXpr>::rootSteps(const IndexId<I>& id) const
-    {
+	template <class CXpr>
+	template <SizeT I>
+	constexpr decltype(auto) RContraction<CXpr>::rootSteps(const IndexId<I>& id) const
+	{
 
-    }
-    
-}
+	}
+
+    } // namespace mpi    
+} // namespace CNORXZ
diff --git a/src/opt/mpi/include/rop_types.h b/src/opt/mpi/include/rop_types.h
index c9f8406..814e0fd 100644
--- a/src/opt/mpi/include/rop_types.h
+++ b/src/opt/mpi/include/rop_types.h
@@ -14,67 +14,70 @@
 
 namespace CNORXZ
 {
-    template <typename T, class IndexT>
-    class CROpRoot : public COpInterface<CROpRoot<T,IndexT>>
+    namespace mpi
     {
-    public:
-	typedef COpInterface<CROpRoot<T,IndexT>> OI;
+	template <typename T, class IndexT>
+	class CROpRoot : public COpInterface<CROpRoot<T,IndexT>>
+	{
+	public:
+	    typedef COpInterface<CROpRoot<T,IndexT>> OI;
 
-	constexpr CROpRoot() = default;
+	    constexpr CROpRoot() = default;
 
-    	template <class PosT>
-	constexpr decltype(auto) operator()(const PosT& pos) const;
+	    template <class PosT>
+	    constexpr decltype(auto) operator()(const PosT& pos) const;
 
-	constexpr decltype(auto) operator()() const;
+	    constexpr decltype(auto) operator()() const;
 
-	template <SizeT I>
-	constexpr decltype(auto) rootSteps(const IndexId<I>& id) const;
+	    template <SizeT I>
+	    constexpr decltype(auto) rootSteps(const IndexId<I>& id) const;
 
-    private:
-	const T* mData;
-	COpRoot
-    };
+	private:
+	    const T* mData;
+	    COpRoot
+	};
 
-    template <typename T, class IndexT>
-    class ROpRoot : public OpInterface<ROpRoot<T,IndexT>>
-    {
-    public:
-	typedef OpInterface<ROpRoot<T,IndexT>> OI;
+	template <typename T, class IndexT>
+	class ROpRoot : public OpInterface<ROpRoot<T,IndexT>>
+	{
+	public:
+	    typedef OpInterface<ROpRoot<T,IndexT>> OI;
 
-	constexpr ROpRoot() = default;
+	    constexpr ROpRoot() = default;
 
-	template <class PosT>
-	constexpr decltype(auto) operator()(const PosT& pos) const;
+	    template <class PosT>
+	    constexpr decltype(auto) operator()(const PosT& pos) const;
 
-	constexpr decltype(auto) operator()() const;
+	    constexpr decltype(auto) operator()() const;
 
-	template <SizeT I>
-	constexpr decltype(auto) rootSteps(const IndexId<I>& id) const;
+	    template <SizeT I>
+	    constexpr decltype(auto) rootSteps(const IndexId<I>& id) const;
 
-    private:
+	private:
 	
-    };
+	};
 
-    template <class CXpr>
-    class RContraction : public OpInterfacte<RContraction<CXpr>>
-    {
-    public:
-	typedef OpInterfacte<RContraction<CXpr>> OI;
+	template <class CXpr>
+	class RContraction : public OpInterfacte<RContraction<CXpr>>
+	{
+	public:
+	    typedef OpInterfacte<RContraction<CXpr>> OI;
 
-	constexpr RContraction() = default;
-	constexpr RContraction(CXpr&& cxpr);
+	    constexpr RContraction() = default;
+	    constexpr RContraction(CXpr&& cxpr);
 
-	template <class PosT>
-	constexpr decltype(auto) operator()(const PosT& pos) const;
+	    template <class PosT>
+	    constexpr decltype(auto) operator()(const PosT& pos) const;
 
-	constexpr decltype(auto) operator()() const;
+	    constexpr decltype(auto) operator()() const;
 
-	template <SizeT I>
-	constexpr decltype(auto) rootSteps(const IndexId<I>& id) const;
+	    template <SizeT I>
+	    constexpr decltype(auto) rootSteps(const IndexId<I>& id) const;
 
-    private:
-	CXpr mCXpr;
-    };
-}
+	private:
+	    CXpr mCXpr;
+	};
+    } // namespace mpi
+} // namespace CNORXZ
 
 #endif
diff --git a/src/opt/mpi/include/rrange.cc.h b/src/opt/mpi/include/rrange.cc.h
index 18c0c5f..986cea1 100644
--- a/src/opt/mpi/include/rrange.cc.h
+++ b/src/opt/mpi/include/rrange.cc.h
@@ -56,9 +56,9 @@ namespace CNORXZ
 	template <class IndexI, class IndexK>
 	RIndex<IndexI,IndexK>& RIndex<IndexI,IndexK>::operator=(SizeT pos)
 	{
-	    IB::mPos = pos; // = lex
-	    if(pos >= lmax().val()){
-		IB::mPos = pmax().val();
+	    mLex = pos; // = lex
+	    if(mLex >= lmax().val()){
+		mLex = lmax().val();
 		return *this;
 	    }
 	    // pos is the lexicographic position of the global range.
@@ -72,7 +72,7 @@ namespace CNORXZ
 	    if constexpr(has_static_sub<IndexI>::value){
 		constexpr SizeT NI = index_dim<IndexI>::value;
 		iter<0,NI>( [&](auto mu) {
-		    const SizeT jmu = (IB::mPos / (ilf[mu].val()*klf[mu].val())) %
+		    const SizeT jmu = (mLex / (ilf[mu].val()*klf[mu].val())) %
 			(i[mu]->lmax().val() * k[mu]->lmax().val());
 		    r += ( jmu / i[mu]->lmax().val() ) * klf[mu].val();
 		    l += ( jmu % i[mu]->lmax().val() ) * ilf[mu].val();
@@ -81,7 +81,7 @@ namespace CNORXZ
 	    else if constexpr( has_static_sub<IndexK>::value){
 		constexpr SizeT NI = index_dim<IndexK>::value;
 		iter<0,NI>( [&](auto mu) {
-		    const SizeT jmu = (IB::mPos / (ilf[mu].val()*klf[mu].val())) %
+		    const SizeT jmu = (mLex / (ilf[mu].val()*klf[mu].val())) %
 			(i[mu]->lmax().val() * k[mu]->lmax().val());
 		    r += ( jmu / i[mu]->lmax().val() ) * klf[mu].val();
 		    l += ( jmu % i[mu]->lmax().val() ) * ilf[mu].val();
@@ -90,7 +90,7 @@ namespace CNORXZ
 	    else {
 		const SizeT NI = mI->dim();
 		for(SizeT mu = 0; mu != NI; ++mu){
-		    const SizeT jmu = (IB::mPos / (ilf[mu].val()*klf[mu].val())) %
+		    const SizeT jmu = (mLex / (ilf[mu].val()*klf[mu].val())) %
 			(i[mu]->lmax().val() * k[mu]->lmax().val());
 		    r += ( jmu / i[mu]->lmax().val() ) * klf[mu].val();
 		    l += ( jmu % i[mu]->lmax().val() ) * ilf[mu].val();
@@ -98,6 +98,7 @@ namespace CNORXZ
 	    }
 	    *mI = l;
 	    *mK = r;
+	    IB::mPos = mK->pos() * mI->pmax().val() + mI->pos();
 	    return *this;
 	}
 
@@ -152,13 +153,13 @@ namespace CNORXZ
 	template <class IndexI, class IndexK>
 	SizeT RIndex<IndexI,IndexK>::lex() const
 	{
-	    return IB::mPos;
+	    return mLex;
 	}
 
 	template <class IndexI, class IndexK>
 	constexpr decltype(auto) RIndex<IndexI,IndexK>::pmax() const
 	{
-	    return UPos(mK->lmax().val() * mI->lmax().val());
+	    return UPos(mK->pmax().val() * mI->pmax().val());
 	}
 
 	template <class IndexI, class IndexK>
@@ -302,11 +303,11 @@ namespace CNORXZ
 	RIndex<IndexI,IndexK>& RIndex<IndexI,IndexK>::operator()()
 	{
 	    if(mI->lex() >= mI->lmax().val()){
-		IB::mPos = lmax().val();
+		mLex = lmax().val();
 	    }
 	    if constexpr(has_static_sub<IndexI>::value){
 		constexpr SizeT NI = index_dim<IndexI>::value;
-		IB::mPos = iter<0,NI>
+		mLex = iter<0,NI>
 		    ([&](auto i) {
 			return mK->pack()[i]->lex() * mK->lexFormat()[i].val() *
 			    mI->lexFormat()[i].val() * mI->pack()[i]->lmax().val() +
@@ -316,7 +317,7 @@ namespace CNORXZ
 	    }
 	    else if constexpr( has_static_sub<IndexK>::value){
 		constexpr SizeT NI = index_dim<IndexK>::value;
-		IB::mPos = iter<0,NI>
+		mLex = iter<0,NI>
 		    ([&](auto i) {
 			return mK->pack()[i]->lex() * mK->lexFormat()[i].val() *
 			    mI->lexFormat()[i].val() * mI->pack()[i]->lmax().val() +
@@ -326,14 +327,15 @@ namespace CNORXZ
 	    }
 	    else {
 		const SizeT NI = mI->dim();
-		IB::mPos = 0;
+		mLex = 0;
 		for(SizeT i = 0; i != NI; ++i){
-		    IB::mPos += mK->pack()[i]->lex() * mK->lexFormat()[i].val() *
+		    mLex += mK->pack()[i]->lex() * mK->lexFormat()[i].val() *
 			mI->lexFormat()[i].val() * mI->pack()[i]->lmax().val() +
 			mI->pack()[i]->lex() * mI->lexFormat()[i].val() *
 			mK->lexFormat()[i].val();
 		}
 	    }
+	    IB::mPos = mK->pos() * mI->pmax().val() + mI->pos();
 	    return *this;
 	}
 
diff --git a/src/opt/mpi/include/rrange.h b/src/opt/mpi/include/rrange.h
index 3aa0767..1179642 100644
--- a/src/opt/mpi/include/rrange.h
+++ b/src/opt/mpi/include/rrange.h
@@ -146,6 +146,7 @@ namespace CNORXZ
 	    Sptr<IndexI> local() const;
 	
 	private:
+	    SizeT mLex = 0;
 	    Sptr<RangeType> mRange; /**< RRange. */
 	    Sptr<IndexI> mI; /**< Index on the local range of the THIS rank. */
 	    Sptr<IndexK> mK; /**< Multi-index indicating the current rank. */