Add numerics/numeric_traits.cpp

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>

src/numerics/numeric_traits.cpp

@@ -0,0 +1,24 @@
+/*
+Copyright (c) 2013 Microsoft Corporation. All rights reserved. 
+Released under Apache 2.0 license as described in the file LICENSE.
+
+Author: Leonardo de Moura 
+*/
+#include <cfenv>
+#include <cmath>
+#include "numeric_traits.h"
+
+namespace lean {
+
+void set_processor_rounding(bool plus_inf) { 
+    if (plus_inf)
+        std::fesetround(FE_UPWARD);
+    else
+        std::fesetround(FE_DOWNWARD);
+}
+
+void double_power(double & v, unsigned k) {
+    v = std::pow(v, k);
+}
+
+};