Please, help us to better know about our user community by answering the following short survey: https://forms.gle/wpyrxWi18ox9Z5ae9
Eigen  3.4.0
 
Loading...
Searching...
No Matches
NullaryFunctors.h
1// This file is part of Eigen, a lightweight C++ template library
2// for linear algebra.
3//
4// Copyright (C) 2008-2016 Gael Guennebaud <gael.guennebaud@inria.fr>
5//
6// This Source Code Form is subject to the terms of the Mozilla
7// Public License v. 2.0. If a copy of the MPL was not distributed
8// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
9
10#ifndef EIGEN_NULLARY_FUNCTORS_H
11#define EIGEN_NULLARY_FUNCTORS_H
12
13namespace Eigen {
14
15namespace internal {
16
17template<typename Scalar>
18struct scalar_constant_op {
19 EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE scalar_constant_op(const scalar_constant_op& other) : m_other(other.m_other) { }
20 EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE scalar_constant_op(const Scalar& other) : m_other(other) { }
21 EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Scalar operator() () const { return m_other; }
22 template<typename PacketType>
23 EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const PacketType packetOp() const { return internal::pset1<PacketType>(m_other); }
24 const Scalar m_other;
25};
26template<typename Scalar>
27struct functor_traits<scalar_constant_op<Scalar> >
28{ enum { Cost = 0 /* as the constant value should be loaded in register only once for the whole expression */,
29 PacketAccess = packet_traits<Scalar>::Vectorizable, IsRepeatable = true }; };
30
31template<typename Scalar> struct scalar_identity_op {
32 EIGEN_EMPTY_STRUCT_CTOR(scalar_identity_op)
33 template<typename IndexType>
34 EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Scalar operator() (IndexType row, IndexType col) const { return row==col ? Scalar(1) : Scalar(0); }
35};
36template<typename Scalar>
37struct functor_traits<scalar_identity_op<Scalar> >
38{ enum { Cost = NumTraits<Scalar>::AddCost, PacketAccess = false, IsRepeatable = true }; };
39
40template <typename Scalar, bool IsInteger> struct linspaced_op_impl;
41
42template <typename Scalar>
43struct linspaced_op_impl<Scalar,/*IsInteger*/false>
44{
45 typedef typename NumTraits<Scalar>::Real RealScalar;
46
47 EIGEN_DEVICE_FUNC linspaced_op_impl(const Scalar& low, const Scalar& high, Index num_steps) :
48 m_low(low), m_high(high), m_size1(num_steps==1 ? 1 : num_steps-1), m_step(num_steps==1 ? Scalar() : Scalar((high-low)/RealScalar(num_steps-1))),
49 m_flip(numext::abs(high)<numext::abs(low))
50 {}
51
52 template<typename IndexType>
53 EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Scalar operator() (IndexType i) const {
54 if(m_flip)
55 return (i==0)? m_low : Scalar(m_high - RealScalar(m_size1-i)*m_step);
56 else
57 return (i==m_size1)? m_high : Scalar(m_low + RealScalar(i)*m_step);
58 }
59
60 template<typename Packet, typename IndexType>
61 EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Packet packetOp(IndexType i) const
62 {
63 // Principle:
64 // [low, ..., low] + ( [step, ..., step] * ( [i, ..., i] + [0, ..., size] ) )
65 if(m_flip)
66 {
67 Packet pi = plset<Packet>(Scalar(i-m_size1));
68 Packet res = padd(pset1<Packet>(m_high), pmul(pset1<Packet>(m_step), pi));
69 if (EIGEN_PREDICT_TRUE(i != 0)) return res;
70 Packet mask = pcmp_lt(pset1<Packet>(0), plset<Packet>(0));
71 return pselect<Packet>(mask, res, pset1<Packet>(m_low));
72 }
73 else
74 {
75 Packet pi = plset<Packet>(Scalar(i));
76 Packet res = padd(pset1<Packet>(m_low), pmul(pset1<Packet>(m_step), pi));
77 if(EIGEN_PREDICT_TRUE(i != m_size1-unpacket_traits<Packet>::size+1)) return res;
78 Packet mask = pcmp_lt(plset<Packet>(0), pset1<Packet>(unpacket_traits<Packet>::size-1));
79 return pselect<Packet>(mask, res, pset1<Packet>(m_high));
80 }
81 }
82
83 const Scalar m_low;
84 const Scalar m_high;
85 const Index m_size1;
86 const Scalar m_step;
87 const bool m_flip;
88};
89
90template <typename Scalar>
91struct linspaced_op_impl<Scalar,/*IsInteger*/true>
92{
93 EIGEN_DEVICE_FUNC linspaced_op_impl(const Scalar& low, const Scalar& high, Index num_steps) :
94 m_low(low),
95 m_multiplier((high-low)/convert_index<Scalar>(num_steps<=1 ? 1 : num_steps-1)),
96 m_divisor(convert_index<Scalar>((high>=low?num_steps:-num_steps)+(high-low))/((numext::abs(high-low)+1)==0?1:(numext::abs(high-low)+1))),
97 m_use_divisor(num_steps>1 && (numext::abs(high-low)+1)<num_steps)
98 {}
99
100 template<typename IndexType>
101 EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE
102 const Scalar operator() (IndexType i) const
103 {
104 if(m_use_divisor) return m_low + convert_index<Scalar>(i)/m_divisor;
105 else return m_low + convert_index<Scalar>(i)*m_multiplier;
106 }
107
108 const Scalar m_low;
109 const Scalar m_multiplier;
110 const Scalar m_divisor;
111 const bool m_use_divisor;
112};
113
114// ----- Linspace functor ----------------------------------------------------------------
115
116// Forward declaration (we default to random access which does not really give
117// us a speed gain when using packet access but it allows to use the functor in
118// nested expressions).
119template <typename Scalar> struct linspaced_op;
120template <typename Scalar> struct functor_traits< linspaced_op<Scalar> >
121{
122 enum
123 {
124 Cost = 1,
125 PacketAccess = (!NumTraits<Scalar>::IsInteger) && packet_traits<Scalar>::HasSetLinear && packet_traits<Scalar>::HasBlend,
126 /*&& ((!NumTraits<Scalar>::IsInteger) || packet_traits<Scalar>::HasDiv),*/ // <- vectorization for integer is currently disabled
127 IsRepeatable = true
128 };
129};
130template <typename Scalar> struct linspaced_op
131{
132 EIGEN_DEVICE_FUNC linspaced_op(const Scalar& low, const Scalar& high, Index num_steps)
133 : impl((num_steps==1 ? high : low),high,num_steps)
134 {}
135
136 template<typename IndexType>
137 EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Scalar operator() (IndexType i) const { return impl(i); }
138
139 template<typename Packet,typename IndexType>
140 EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Packet packetOp(IndexType i) const { return impl.template packetOp<Packet>(i); }
141
142 // This proxy object handles the actual required temporaries and the different
143 // implementations (integer vs. floating point).
144 const linspaced_op_impl<Scalar,NumTraits<Scalar>::IsInteger> impl;
145};
146
147// Linear access is automatically determined from the operator() prototypes available for the given functor.
148// If it exposes an operator()(i,j), then we assume the i and j coefficients are required independently
149// and linear access is not possible. In all other cases, linear access is enabled.
150// Users should not have to deal with this structure.
151template<typename Functor> struct functor_has_linear_access { enum { ret = !has_binary_operator<Functor>::value }; };
152
153// For unreliable compilers, let's specialize the has_*ary_operator
154// helpers so that at least built-in nullary functors work fine.
155#if !( (EIGEN_COMP_MSVC>1600) || (EIGEN_GNUC_AT_LEAST(4,8)) || (EIGEN_COMP_ICC>=1600))
156template<typename Scalar,typename IndexType>
157struct has_nullary_operator<scalar_constant_op<Scalar>,IndexType> { enum { value = 1}; };
158template<typename Scalar,typename IndexType>
159struct has_unary_operator<scalar_constant_op<Scalar>,IndexType> { enum { value = 0}; };
160template<typename Scalar,typename IndexType>
161struct has_binary_operator<scalar_constant_op<Scalar>,IndexType> { enum { value = 0}; };
162
163template<typename Scalar,typename IndexType>
164struct has_nullary_operator<scalar_identity_op<Scalar>,IndexType> { enum { value = 0}; };
165template<typename Scalar,typename IndexType>
166struct has_unary_operator<scalar_identity_op<Scalar>,IndexType> { enum { value = 0}; };
167template<typename Scalar,typename IndexType>
168struct has_binary_operator<scalar_identity_op<Scalar>,IndexType> { enum { value = 1}; };
169
170template<typename Scalar,typename IndexType>
171struct has_nullary_operator<linspaced_op<Scalar>,IndexType> { enum { value = 0}; };
172template<typename Scalar,typename IndexType>
173struct has_unary_operator<linspaced_op<Scalar>,IndexType> { enum { value = 1}; };
174template<typename Scalar,typename IndexType>
175struct has_binary_operator<linspaced_op<Scalar>,IndexType> { enum { value = 0}; };
176
177template<typename Scalar,typename IndexType>
178struct has_nullary_operator<scalar_random_op<Scalar>,IndexType> { enum { value = 1}; };
179template<typename Scalar,typename IndexType>
180struct has_unary_operator<scalar_random_op<Scalar>,IndexType> { enum { value = 0}; };
181template<typename Scalar,typename IndexType>
182struct has_binary_operator<scalar_random_op<Scalar>,IndexType> { enum { value = 0}; };
183#endif
184
185} // end namespace internal
186
187} // end namespace Eigen
188
189#endif // EIGEN_NULLARY_FUNCTORS_H
Namespace containing all symbols from the Eigen library.
Definition: Core:141
EIGEN_DEFAULT_DENSE_INDEX_TYPE Index
The Index type as used for the API.
Definition: Meta.h:74