From 1417a8acd21c80ac852bfd86dc160534c272ecd2 Mon Sep 17 00:00:00 2001
From: bolero-MURAKAMI <bolero.murakami@gmail.com>
Date: Fri, 4 May 2012 18:21:18 +0900
Subject: [PATCH] add sprout::exp2, expm1

---
 sprout/math/exp10.hpp       | 38 +++++++++++++++++++++++++++++++
 sprout/math/exp2.hpp        | 45 +++++++++++++++++++++++++++++++++++++
 sprout/math/expm1.hpp       | 45 +++++++++++++++++++++++++++++++++++++
 sprout/math/exponential.hpp |  3 +++
 4 files changed, 131 insertions(+)
 create mode 100644 sprout/math/exp10.hpp
 create mode 100644 sprout/math/exp2.hpp
 create mode 100644 sprout/math/expm1.hpp

diff --git a/sprout/math/exp10.hpp b/sprout/math/exp10.hpp
new file mode 100644
index 00000000..350014a8
--- /dev/null
+++ b/sprout/math/exp10.hpp
@@ -0,0 +1,38 @@
+#ifndef SPROUT_MATH_EXP10_HPP
+#define SPROUT_MATH_EXP10_HPP
+
+#include <type_traits>
+#include <sprout/config.hpp>
+#include <sprout/math/exp.hpp>
+#include <sprout/math/constants.hpp>
+#include <sprout/utility/enabler_if.hpp>
+
+namespace sprout {
+	namespace math {
+		namespace detail {
+			template<
+				typename FloatType,
+				typename sprout::enabler_if<std::is_floating_point<FloatType>::value>::type = sprout::enabler
+			>
+			inline SPROUT_CONSTEXPR FloatType
+			exp10(FloatType x) {
+				return sprout::math::detail::exp(x * sprout::math::ln_ten<FloatType>());
+			}
+
+			template<
+				typename IntType,
+				typename sprout::enabler_if<std::is_integral<IntType>::value>::type = sprout::enabler
+			>
+			inline SPROUT_CONSTEXPR double
+			exp10(IntType x) {
+				return sprout::math::detail::exp10(static_cast<double>(x));
+			}
+		}	// namespace detail
+
+		using sprout::math::detail::exp10;
+	}	// namespace math
+
+	using sprout::math::exp10;
+}	// namespace sprout
+
+#endif	// #ifndef SPROUT_MATH_EXP10_HPP
diff --git a/sprout/math/exp2.hpp b/sprout/math/exp2.hpp
new file mode 100644
index 00000000..f2c3f4b2
--- /dev/null
+++ b/sprout/math/exp2.hpp
@@ -0,0 +1,45 @@
+#ifndef SPROUT_MATH_EXP2_HPP
+#define SPROUT_MATH_EXP2_HPP
+
+#include <type_traits>
+#include <sprout/config.hpp>
+#include <sprout/math/exp.hpp>
+#include <sprout/math/constants.hpp>
+#include <sprout/utility/enabler_if.hpp>
+#if SPROUT_USE_BUILTIN_CMATH_FUNCTION
+#	include <cmath>
+#endif
+
+namespace sprout {
+	namespace math {
+		namespace detail {
+			template<
+				typename FloatType,
+				typename sprout::enabler_if<std::is_floating_point<FloatType>::value>::type = sprout::enabler
+			>
+			inline SPROUT_CONSTEXPR FloatType
+			exp2(FloatType x) {
+				return sprout::math::detail::exp(x * sprout::math::ln_two<FloatType>());
+			}
+
+			template<
+				typename IntType,
+				typename sprout::enabler_if<std::is_integral<IntType>::value>::type = sprout::enabler
+			>
+			inline SPROUT_CONSTEXPR double
+			exp2(IntType x) {
+				return sprout::math::detail::exp2(static_cast<double>(x));
+			}
+		}	// namespace detail
+
+#	if SPROUT_USE_BUILTIN_CMATH_FUNCTION
+		using std::exp2;
+#	else
+		using sprout::math::detail::exp2;
+#	endif
+	}	// namespace math
+
+	using sprout::math::exp2;
+}	// namespace sprout
+
+#endif	// #ifndef SPROUT_MATH_EXP2_HPP
diff --git a/sprout/math/expm1.hpp b/sprout/math/expm1.hpp
new file mode 100644
index 00000000..078c392a
--- /dev/null
+++ b/sprout/math/expm1.hpp
@@ -0,0 +1,45 @@
+#ifndef SPROUT_MATH_EXPM1_HPP
+#define SPROUT_MATH_EXPM1_HPP
+
+#include <type_traits>
+#include <sprout/config.hpp>
+#include <sprout/math/exp.hpp>
+#include <sprout/math/constants.hpp>
+#include <sprout/utility/enabler_if.hpp>
+#if SPROUT_USE_BUILTIN_CMATH_FUNCTION
+#	include <cmath>
+#endif
+
+namespace sprout {
+	namespace math {
+		namespace detail {
+			template<
+				typename FloatType,
+				typename sprout::enabler_if<std::is_floating_point<FloatType>::value>::type = sprout::enabler
+			>
+			inline SPROUT_CONSTEXPR FloatType
+			expm1(FloatType x) {
+				return sprout::math::detail::exp(x) - 1;
+			}
+
+			template<
+				typename IntType,
+				typename sprout::enabler_if<std::is_integral<IntType>::value>::type = sprout::enabler
+			>
+			inline SPROUT_CONSTEXPR double
+			expm1(IntType x) {
+				return sprout::math::detail::expm1(static_cast<double>(x));
+			}
+		}	// namespace detail
+
+#	if SPROUT_USE_BUILTIN_CMATH_FUNCTION
+		using std::expm1;
+#	else
+		using sprout::math::detail::expm1;
+#	endif
+	}	// namespace math
+
+	using sprout::math::expm1;
+}	// namespace sprout
+
+#endif	// #ifndef SPROUT_MATH_EXPM1_HPP
diff --git a/sprout/math/exponential.hpp b/sprout/math/exponential.hpp
index 9cd437de..fc686146 100644
--- a/sprout/math/exponential.hpp
+++ b/sprout/math/exponential.hpp
@@ -2,6 +2,9 @@
 #define SPROUT_MATH_EXPONENTIAL_HPP
 
 #include <sprout/math/exp.hpp>
+#include <sprout/math/exp10.hpp>
+#include <sprout/math/exp2.hpp>
+#include <sprout/math/expm1.hpp>
 #include <sprout/math/log.hpp>
 #include <sprout/math/log10.hpp>
 #include <sprout/math/log2.hpp>