diff --git a/benchmarks/bench2/bench21.cpp b/benchmarks/bench2/bench21.cpp
new file mode 100644
index 0000000..50d70a4
--- /dev/null
+++ b/benchmarks/bench2/bench21.cpp
@@ -0,0 +1,282 @@
+//
+//  Copyright (c) 2000-2002
+//  Joerg Walter, Mathias Koch
+//
+//  Distributed under the Boost Software License, Version 1.0. (See
+//  accompanying file LICENSE_1_0.txt or copy at
+//  http://www.boost.org/LICENSE_1_0.txt)
+//
+//  The authors gratefully acknowledge the support of
+//  GeNeSys mbH & Co. KG in producing this work.
+//
+
+#include "bench2.hpp"
+
+template<class T, int N>
+struct bench_c_inner_prod {
+    typedef T value_type;
+
+    void operator () (int runs) const {
+        try {
+            static typename c_vector_traits<T, N>::type v1, v2;
+            initialize_c_vector<T, N> () (v1);
+            initialize_c_vector<T, N> () (v2);
+            boost::timer t;
+            for (int i = 0; i < runs; ++ i) {
+                static value_type s (0);
+                for (int j = 0; j < N; ++ j) {
+                    s += v1 [j] * v2 [j];
+                }
+//                sink_scalar (s);
+            }
+            footer<value_type> () (N, N - 1, runs, t.elapsed ());
+        }
+        catch (std::exception &e) {
+            std::cout << e.what () << std::endl;
+        }
+    }
+};
+template<class V, int N>
+struct bench_my_inner_prod {
+    typedef typename V::value_type value_type;
+
+    void operator () (int runs) const {
+        try {
+            static V v1 (N, N), v2 (N, N);
+            initialize_vector (v1);
+            initialize_vector (v2);
+            boost::timer t;
+            for (int i = 0; i < runs; ++ i) {
+                static value_type s (0);
+                s = ublas::inner_prod (v1, v2);
+//                sink_scalar (s);
+                BOOST_UBLAS_NOT_USED(s);
+            }
+            footer<value_type> () (N, N - 1, runs, t.elapsed ());
+        }
+        catch (std::exception &e) {
+            std::cout << e.what () << std::endl;
+        }
+    }
+};
+template<class V, int N>
+struct bench_cpp_inner_prod {
+    typedef typename V::value_type value_type;
+
+    void operator () (int runs) const {
+        try {
+            static V v1 (N), v2 (N);
+            initialize_vector (v1);
+            initialize_vector (v2);
+            boost::timer t;
+            for (int i = 0; i < runs; ++ i) {
+                static value_type s (0);
+                s = (v1 * v2).sum ();
+//                sink_scalar (s);
+            }
+            footer<value_type> () (N, N - 1, runs, t.elapsed ());
+        }
+        catch (std::exception &e) {
+            std::cout << e.what () << std::endl;
+        }
+    }
+};
+
+template<class T, int N>
+struct bench_c_vector_add {
+    typedef T value_type;
+
+    void operator () (int runs) const {
+        try {
+            static typename c_vector_traits<T, N>::type v1, v2, v3;
+            initialize_c_vector<T, N> () (v1);
+            initialize_c_vector<T, N> () (v2);
+            boost::timer t;
+            for (int i = 0; i < runs; ++ i) {
+                for (int j = 0; j < N; ++ j) {
+                    v3 [j] = - (v1 [j] + v2 [j]);
+                }
+//                sink_c_vector<T, N> () (v3);
+                BOOST_UBLAS_NOT_USED(v3);
+            }
+            footer<value_type> () (0, 2 * N, runs, t.elapsed ());
+        }
+        catch (std::exception &e) {
+            std::cout << e.what () << std::endl;
+        }
+    }
+};
+template<class V, int N>
+struct bench_my_vector_add {
+    typedef typename V::value_type value_type;
+
+    void operator () (int runs, safe_tag) const {
+        try {
+            static V v1 (N, N), v2 (N, N), v3 (N, N);
+            initialize_vector (v1);
+            initialize_vector (v2);
+            boost::timer t;
+            for (int i = 0; i < runs; ++ i) {
+                v3 = - (v1 + v2);
+//                sink_vector (v3);
+            }
+            footer<value_type> () (0, 2 * N, runs, t.elapsed ());
+        }
+        catch (std::exception &e) {
+            std::cout << e.what () << std::endl;
+        }
+    }
+    void operator () (int runs, fast_tag) const {
+        try {
+            static V v1 (N, N), v2 (N, N), v3 (N, N);
+            initialize_vector (v1);
+            initialize_vector (v2);
+            boost::timer t;
+            for (int i = 0; i < runs; ++ i) {
+                v3.assign (- (v1 + v2));
+//                sink_vector (v3);
+            }
+            footer<value_type> () (0, 2 * N, runs, t.elapsed ());
+        }
+        catch (std::exception &e) {
+            std::cout << e.what () << std::endl;
+        }
+    }
+};
+template<class V, int N>
+struct bench_cpp_vector_add {
+    typedef typename V::value_type value_type;
+
+    void operator () (int runs) const {
+        try {
+            static V v1 (N), v2 (N), v3 (N);
+            initialize_vector (v1);
+            initialize_vector (v2);
+            boost::timer t;
+            for (int i = 0; i < runs; ++ i) {
+                v3 = - (v1 + v2);
+//                sink_vector (v3);
+            }
+            footer<value_type> () (0, 2 * N, runs, t.elapsed ());
+        }
+        catch (std::exception &e) {
+            std::cout << e.what () << std::endl;
+        }
+    }
+};
+
+// Benchmark O (n)
+template<class T, int N>
+void bench_1<T, N>::operator () (int runs) {
+    header ("bench_1");
+
+    header ("inner_prod");
+
+    header ("C array");
+    bench_c_inner_prod<T, N> () (runs);
+
+#ifdef USE_MAPPED_VECTOR
+#ifdef USE_MAP_ARRAY
+    header ("mapped_vector<map_array>");
+    bench_my_inner_prod<ublas::mapped_vector<T, ublas::map_array<std::size_t, T> >, N> () (runs);
+#endif
+
+#ifdef USE_STD_MAP
+    header ("mapped_vector<std::map>");
+    bench_my_inner_prod<ublas::mapped_vector<T, std::map<std::size_t, T> >, N> () (runs);
+#endif
+#endif
+
+#ifdef USE_COMPRESSED_VECTOR
+    header ("compressed_vector");
+    bench_my_inner_prod<ublas::compressed_vector<T>, N> () (runs);
+#endif
+
+#ifdef USE_COORDINATE_VECTOR
+    header ("coordinate_vector");
+    bench_my_inner_prod<ublas::coordinate_vector<T>, N> () (runs);
+#endif
+
+#ifdef USE_STD_VALARRAY
+    header ("std::valarray");
+    bench_cpp_inner_prod<std::valarray<T>, N> () (runs);
+#endif
+
+    header ("vector + vector");
+
+    header ("C array");
+    bench_c_vector_add<T, N> () (runs);
+
+#ifdef USE_MAPPED_VECTOR
+#ifdef USE_MAP_ARRAY
+    header ("mapped_vector<map_array> safe");
+    bench_my_vector_add<ublas::mapped_vector<T, ublas::map_array<std::size_t, T> >, N> () (runs, safe_tag ());
+
+    header ("maped_vector<map_array> fast");
+    bench_my_vector_add<ublas::mapped_vector<T, ublas::map_array<std::size_t, T> >, N> () (runs, fast_tag ());
+#endif
+
+#ifdef USE_STD_MAP
+    header ("mapped_vector<std::map> safe");
+    bench_my_vector_add<ublas::mapped_vector<T, std::map<std::size_t, T> >, N> () (runs, safe_tag ());
+
+    header ("mapped_vector<std::map> fast");
+    bench_my_vector_add<ublas::mapped_vector<T, std::map<std::size_t, T> >, N> () (runs, fast_tag ());
+#endif
+#endif
+
+#ifdef USE_COMPRESSED_VECTOR
+#ifdef USE_MAP_ARRAY
+    header ("compressed_vector safe");
+    bench_my_vector_add<ublas::compressed_vector<T>, N> () (runs, safe_tag ());
+
+    header ("compressed_vector fast");
+    bench_my_vector_add<ublas::compressed_vector<T>, N> () (runs, fast_tag ());
+#endif
+#endif
+
+#ifdef USE_COORDINATE_VECTOR
+#ifdef USE_MAP_ARRAY
+    header ("coordinate_vector safe");
+    bench_my_vector_add<ublas::coordinate_vector<T>, N> () (runs, safe_tag ());
+
+    header ("coordinate_vector fast");
+    bench_my_vector_add<ublas::coordinate_vector<T>, N> () (runs, fast_tag ());
+#endif
+#endif
+
+#ifdef USE_STD_VALARRAY
+    header ("std::valarray");
+    bench_cpp_vector_add<std::valarray<T>, N> () (runs);
+#endif
+}
+
+#ifdef USE_FLOAT
+template struct bench_1<float, 3>;
+template struct bench_1<float, 10>;
+template struct bench_1<float, 30>;
+template struct bench_1<float, 100>;
+#endif
+
+#ifdef USE_DOUBLE
+template struct bench_1<double, 3>;
+template struct bench_1<double, 10>;
+template struct bench_1<double, 30>;
+template struct bench_1<double, 100>;
+#endif
+
+#ifdef USE_STD_COMPLEX
+#ifdef USE_FLOAT
+template struct bench_1<std::complex<float>, 3>;
+template struct bench_1<std::complex<float>, 10>;
+template struct bench_1<std::complex<float>, 30>;
+template struct bench_1<std::complex<float>, 100>;
+#endif
+
+#ifdef USE_DOUBLE
+template struct bench_1<std::complex<double>, 3>;
+template struct bench_1<std::complex<double>, 10>;
+template struct bench_1<std::complex<double>, 30>;
+template struct bench_1<std::complex<double>, 100>;
+#endif
+#endif