--- /dev/null
+// Special functions -*- C++ -*-
+
+// Copyright (C) 2006-2007
+// Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library. This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 2, or (at your option)
+// any later version.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING. If not, write to the Free
+// Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
+// USA.
+//
+// As a special exception, you may use this file as part of a free software
+// library without restriction. Specifically, if other files instantiate
+// templates or use macros or inline functions from this file, or you compile
+// this file and link it with other files to produce an executable, this
+// file does not by itself cause the resulting executable to be covered by
+// the GNU General Public License. This exception does not however
+// invalidate any other reasons why the executable file might be covered by
+// the GNU General Public License.
+
+/** @file tr1/poly_hermite.tcc
+ * This is an internal header file, included by other library headers.
+ * You should not attempt to use it directly.
+ */
+
+//
+// ISO C++ 14882 TR1: 5.2 Special functions
+//
+
+// Written by Edward Smith-Rowland based on:
+// (1) Handbook of Mathematical Functions,
+// Ed. Milton Abramowitz and Irene A. Stegun,
+// Dover Publications, Section 22 pp. 773-802
+
+#ifndef _TR1_POLY_HERMITE_TCC
+#define _TR1_POLY_HERMITE_TCC 1
+
+namespace std
+{
+_GLIBCXX_BEGIN_NAMESPACE(_GLIBCXX_TR1)
+
+ // [5.2] Special functions
+
+ /**
+ * @ingroup tr1_math_spec_func
+ * @{
+ */
+
+ //
+ // Implementation-space details.
+ //
+ namespace __detail
+ {
+
+ /**
+ * @brief This routine returns the Hermite polynomial
+ * of order n: \f$ H_n(x) \f$ by recursion on n.
+ *
+ * The Hermite polynomial is defined by:
+ * @f[
+ * H_n(x) = (-1)^n e^{x^2} \frac{d^n}{dx^n} e^{-x^2}
+ * @f]
+ *
+ * @param __n The order of the Hermite polynomial.
+ * @param __x The argument of the Hermite polynomial.
+ * @return The value of the Hermite polynomial of order n
+ * and argument x.
+ */
+ template<typename _Tp>
+ _Tp
+ __poly_hermite_recursion(const unsigned int __n, const _Tp __x)
+ {
+ // Compute H_0.
+ _Tp __H_0 = 1;
+ if (__n == 0)
+ return __H_0;
+
+ // Compute H_1.
+ _Tp __H_1 = 2 * __x;
+ if (__n == 1)
+ return __H_1;
+
+ // Compute H_n.
+ _Tp __H_n, __H_nm1, __H_nm2;
+ unsigned int __i;
+ for (__H_nm2 = __H_0, __H_nm1 = __H_1, __i = 2; __i <= __n; ++__i)
+ {
+ __H_n = 2 * (__x * __H_nm1 + (__i - 1) * __H_nm2);
+ __H_nm2 = __H_nm1;
+ __H_nm1 = __H_n;
+ }
+
+ return __H_n;
+ }
+
+
+ /**
+ * @brief This routine returns the Hermite polynomial
+ * of order n: \f$ H_n(x) \f$.
+ *
+ * The Hermite polynomial is defined by:
+ * @f[
+ * H_n(x) = (-1)^n e^{x^2} \frac{d^n}{dx^n} e^{-x^2}
+ * @f]
+ *
+ * @param __n The order of the Hermite polynomial.
+ * @param __x The argument of the Hermite polynomial.
+ * @return The value of the Hermite polynomial of order n
+ * and argument x.
+ */
+ template<typename _Tp>
+ inline _Tp
+ __poly_hermite(const unsigned int __n, const _Tp __x)
+ {
+ if (__isnan(__x))
+ return std::numeric_limits<_Tp>::quiet_NaN();
+ else
+ return __poly_hermite_recursion(__n, __x);
+ }
+
+ } // namespace std::tr1::__detail
+
+ /* @} */ // group tr1_math_spec_func
+
+_GLIBCXX_END_NAMESPACE
+}
+
+#endif // _TR1_POLY_HERMITE_TCC
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