Update MatGeneric::to_string for MatPerm and MatButterfly compatibility.

src/faust_linear_operator/faust_MatGeneric.hpp

@@ -43,6 +43,8 @@
 // useful for optimize with multiplication
 #include "faust_Timer.h"
 #include "faust_MatBSR.h"
+#include "faust_MatPerm.h"
+#include "faust_MatButterfly.h"
 
 
 template<typename FPP,FDevice DEVICE>
@@ -151,6 +153,10 @@ std::string Faust::MatGeneric<FPP,DEVICE>::to_string(const bool transpose /* set
 		type = Diag;
 	else if (dynamic_cast<const MatBSR<FPP, DEVICE>*>(this))
 		type = BSR;
+	else if (dynamic_cast<const MatPerm<FPP, DEVICE>*>(this))
+		type = Perm;
+	else if (dynamic_cast<const MatButterfly<FPP, DEVICE>*>(this))
+		type = Butterfly;
 	else
 		throw std::runtime_error("Unhandled matrix type in MatGeneric::to_string()"); // shouldn't happen
 	return this->to_string(getNbRow(), getNbCol(), transpose, this->density(), this->getNonZeros(), this->is_identity, type);
@@ -186,6 +192,10 @@ std::string Faust::MatGeneric<FPP,DEVICE>::to_string(int32_t nrows, int32_t ncol
 		str << "DIAG,";
 	else if(type == BSR)
 		str << "BSR,";
+	else if(type == Perm)
+		str << "PERM,";
+	else if(type == Butterfly)
+		str << "Butterfly,";
 	else if(type == None)
 		str << "UNKNOWN MATRIX TYPE,";
 	else