You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
117 lines
2.1 KiB
117 lines
2.1 KiB
// This file is part of Eigen, a lightweight C++ template library |
|
// for linear algebra. |
|
// |
|
// Copyright (C) 2010, 2013 Jitse Niesen <jitse@maths.leeds.ac.uk> |
|
// |
|
// 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 the mozilla.org home page |
|
|
|
#ifndef EIGEN_STEM_FUNCTION |
|
#define EIGEN_STEM_FUNCTION |
|
|
|
namespace Eigen { |
|
|
|
namespace internal { |
|
|
|
/** \brief The exponential function (and its derivatives). */ |
|
template <typename Scalar> |
|
Scalar stem_function_exp(Scalar x, int) |
|
{ |
|
using std::exp; |
|
return exp(x); |
|
} |
|
|
|
/** \brief Cosine (and its derivatives). */ |
|
template <typename Scalar> |
|
Scalar stem_function_cos(Scalar x, int n) |
|
{ |
|
using std::cos; |
|
using std::sin; |
|
Scalar res; |
|
|
|
switch (n % 4) { |
|
case 0: |
|
res = std::cos(x); |
|
break; |
|
case 1: |
|
res = -std::sin(x); |
|
break; |
|
case 2: |
|
res = -std::cos(x); |
|
break; |
|
case 3: |
|
res = std::sin(x); |
|
break; |
|
} |
|
return res; |
|
} |
|
|
|
/** \brief Sine (and its derivatives). */ |
|
template <typename Scalar> |
|
Scalar stem_function_sin(Scalar x, int n) |
|
{ |
|
using std::cos; |
|
using std::sin; |
|
Scalar res; |
|
|
|
switch (n % 4) { |
|
case 0: |
|
res = std::sin(x); |
|
break; |
|
case 1: |
|
res = std::cos(x); |
|
break; |
|
case 2: |
|
res = -std::sin(x); |
|
break; |
|
case 3: |
|
res = -std::cos(x); |
|
break; |
|
} |
|
return res; |
|
} |
|
|
|
/** \brief Hyperbolic cosine (and its derivatives). */ |
|
template <typename Scalar> |
|
Scalar stem_function_cosh(Scalar x, int n) |
|
{ |
|
using std::cosh; |
|
using std::sinh; |
|
Scalar res; |
|
|
|
switch (n % 2) { |
|
case 0: |
|
res = std::cosh(x); |
|
break; |
|
case 1: |
|
res = std::sinh(x); |
|
break; |
|
} |
|
return res; |
|
} |
|
|
|
/** \brief Hyperbolic sine (and its derivatives). */ |
|
template <typename Scalar> |
|
Scalar stem_function_sinh(Scalar x, int n) |
|
{ |
|
using std::cosh; |
|
using std::sinh; |
|
Scalar res; |
|
|
|
switch (n % 2) { |
|
case 0: |
|
res = std::sinh(x); |
|
break; |
|
case 1: |
|
res = std::cosh(x); |
|
break; |
|
} |
|
return res; |
|
} |
|
|
|
} // end namespace internal |
|
|
|
} // end namespace Eigen |
|
|
|
#endif // EIGEN_STEM_FUNCTION
|
|
|