Add new accessor

core/base/extended_float.hpp

@@ -34,6 +34,7 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #define GKO_CORE_BASE_EXTENDED_FLOAT_HPP_
 
 
+#include <limits>
 #include <type_traits>
 
 
@@ -550,6 +551,31 @@ class complex<gko::truncated<T, NumComponents>> {
 };
 
 
+template <>
+struct is_scalar<gko::half> : std::true_type {};
+
+
+template <>
+struct numeric_limits<gko::half> {
+    static constexpr bool is_specialized{true};
+    static constexpr bool is_signed{true};
+    static constexpr bool is_integer{false};
+    static constexpr bool is_exact{false};
+    static constexpr bool is_bounded{true};
+    static constexpr bool is_modulo{false};
+    static constexpr int digits{
+        gko::detail::float_traits<gko::half>::significand_bits + 1};
+    // 3/10 is approx. log_10(2)
+    static constexpr int digits10{digits * 3 / 10};
+
+    // Note: gko::half can't return gko::half here because it does not have
+    //       a constexpr constructor.
+    static constexpr float epsilon()
+    {
+        return gko::detail::float_traits<gko::half>::eps;
+    }
+};
+
 }  // namespace std
 
 

core/test/base/CMakeLists.txt

@@ -1,4 +1,5 @@
 ginkgo_create_test(abstract_factory)
+ginkgo_create_test(accessors_reduced_storage)
 ginkgo_create_test(allocator)
 ginkgo_create_test(array)
 ginkgo_create_test(combination)