diff --git a/libsrc/general/archive_base.hpp b/libsrc/general/archive_base.hpp
index f6e18cea..9531c7ac 100644
--- a/libsrc/general/archive_base.hpp
+++ b/libsrc/general/archive_base.hpp
@@ -1,6 +1,8 @@
 #ifndef NGS_ARCHIVE_BASE
 #define NGS_ARCHIVE_BASE
 
+// copied from netgen
+
 namespace ngstd
 {
 
@@ -20,6 +22,37 @@ namespace ngstd
     virtual Archive & operator & (string & str) = 0;
     virtual Archive & operator & (char *& str) = 0;
 
+    template <typename T>
+    Archive & Do (T * data, size_t n) 
+    { for (size_t j = 0; j < n; j++) { (*this) & data[j]; }; return *this; };
+
+
+    virtual Archive & Do (double * d, size_t n) 
+    { for (size_t j = 0; j < n; j++) { (*this) & d[j]; }; return *this; };
+
+    virtual Archive & Do (int * i, size_t n) 
+    { for (size_t j = 0; j < n; j++) { (*this) & i[j]; }; return *this; };
+
+    virtual Archive & Do (long * i, size_t n)
+    { for (size_t j = 0; j < n; j++) { (*this) & i[j]; }; return *this; };
+
+    virtual Archive & Do (size_t * i, size_t n) 
+    { for (size_t j = 0; j < n; j++) { (*this) & i[j]; }; return *this; };
+
+    virtual Archive & Do (short * i, size_t n) 
+    { for (size_t j = 0; j < n; j++) { (*this) & i[j]; }; return *this; };
+
+    virtual Archive & Do (unsigned char * i, size_t n)
+    { for (size_t j = 0; j < n; j++) { (*this) & i[j]; }; return *this; };
+
+    virtual Archive & Do (bool * b, size_t n)
+    { for (size_t j = 0; j < n; j++) { (*this) & b[j]; }; return *this; };
+
+
+    // nvirtual Archive & Do (string * str, size_t n)
+    // { for (size_t j = 0; j < n; j++) { (*this) & str[j]; }; return *this; };
+    // virtual Archive & operator & (char *& str) = 0;
+
     template <typename T>
     Archive & operator << (const T & t)
     {