Squashed 'third_party/eigen/' content from commit 61d72f6

Change-Id: Iccc90fa0b55ab44037f018046d2fcffd90d9d025
git-subtree-dir: third_party/eigen
git-subtree-split: 61d72f6383cfa842868c53e30e087b0258177257
diff --git a/Eigen/src/Eigen2Support/MathFunctions.h b/Eigen/src/Eigen2Support/MathFunctions.h
new file mode 100644
index 0000000..3544af2
--- /dev/null
+++ b/Eigen/src/Eigen2Support/MathFunctions.h
@@ -0,0 +1,57 @@
+// This file is part of Eigen, a lightweight C++ template library
+// for linear algebra.
+//
+// Copyright (C) 2010 Gael Guennebaud <gael.guennebaud@inria.fr>
+//
+// This Source Code Form is subject to the terms of the Mozilla
+// Public License v. 2.0. If a copy of the MPL was not distributed
+// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+#ifndef EIGEN2_MATH_FUNCTIONS_H
+#define EIGEN2_MATH_FUNCTIONS_H
+
+namespace Eigen { 
+
+template<typename T> inline typename NumTraits<T>::Real ei_real(const T& x) { return numext::real(x); }
+template<typename T> inline typename NumTraits<T>::Real ei_imag(const T& x) { return numext::imag(x); }
+template<typename T> inline T ei_conj(const T& x) { return numext::conj(x); }
+template<typename T> inline typename NumTraits<T>::Real ei_abs (const T& x) { using std::abs; return abs(x); }
+template<typename T> inline typename NumTraits<T>::Real ei_abs2(const T& x) { return numext::abs2(x); }
+template<typename T> inline T ei_sqrt(const T& x) { using std::sqrt; return sqrt(x); }
+template<typename T> inline T ei_exp (const T& x) { using std::exp;  return exp(x); }
+template<typename T> inline T ei_log (const T& x) { using std::log;  return log(x); }
+template<typename T> inline T ei_sin (const T& x) { using std::sin;  return sin(x); }
+template<typename T> inline T ei_cos (const T& x) { using std::cos;  return cos(x); }
+template<typename T> inline T ei_atan2(const T& x,const T& y) { using std::atan2; return atan2(x,y); }
+template<typename T> inline T ei_pow (const T& x,const T& y) { return numext::pow(x,y); }
+template<typename T> inline T ei_random () { return internal::random<T>(); }
+template<typename T> inline T ei_random (const T& x, const T& y) { return internal::random(x, y); }
+
+template<typename T> inline T precision () { return NumTraits<T>::dummy_precision(); }
+template<typename T> inline T machine_epsilon () { return NumTraits<T>::epsilon(); }
+
+
+template<typename Scalar, typename OtherScalar>
+inline bool ei_isMuchSmallerThan(const Scalar& x, const OtherScalar& y,
+                                   typename NumTraits<Scalar>::Real precision = NumTraits<Scalar>::dummy_precision())
+{
+  return internal::isMuchSmallerThan(x, y, precision);
+}
+
+template<typename Scalar>
+inline bool ei_isApprox(const Scalar& x, const Scalar& y,
+                          typename NumTraits<Scalar>::Real precision = NumTraits<Scalar>::dummy_precision())
+{
+  return internal::isApprox(x, y, precision);
+}
+
+template<typename Scalar>
+inline bool ei_isApproxOrLessThan(const Scalar& x, const Scalar& y,
+                                    typename NumTraits<Scalar>::Real precision = NumTraits<Scalar>::dummy_precision())
+{
+  return internal::isApproxOrLessThan(x, y, precision);
+}
+
+} // end namespace Eigen
+
+#endif // EIGEN2_MATH_FUNCTIONS_H