fixed permutation matrices

mat.h

@@ -139,7 +139,7 @@ public:
 	void axpy(const T alpha, const NRPerm<int> &p, const bool direction);
 	explicit NRMat(const NRPerm<int> &p, const bool direction, const bool parity=false); //permutation matrix
 	explicit NRMat(const WeightPermutation<int,T> &p, const bool direction); 
-	explicit NRMat(const PermutationAlgebra<int,T> &p, const bool direction); 
+	explicit NRMat(const PermutationAlgebra<int,T> &p, const bool direction, const int nforce=0); //note that one cannot represent e.g. young projectors in this way, since the representation of S(n) by permutation matrices is reducible just to two irreps [n] and [n-1,1]
 
 
 	/***************************************************************************//**
@@ -1167,6 +1167,7 @@ void NRMat<T>::copyonwrite(bool detachonly) {
  * @see count, NRMat<T>::copyonwrite(), NRMat<T>::operator|=() 
  * @return reference to the newly copied matrix 
  ******************************************************************************/
+//NOTE it must not be used in constructors when the data were not initialized yet
 template <typename T>
 void NRMat<T>::resize(int n, int m) {
 #ifdef DEBUG