eigen/unsupported/Eigen/CXX11/src/Tensor/TensorDimensions.h
2014-07-10 11:29:51 -07:00

270 lines
9.5 KiB
C++

// This file is part of Eigen, a lightweight C++ template library
// for linear algebra.
//
// Copyright (C) 2014 Benoit Steiner <benoit.steiner.goog@gmail.com>
//
// 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 EIGEN_CXX11_TENSOR_TENSOR_DIMENSIONS_H
#define EIGEN_CXX11_TENSOR_TENSOR_DIMENSIONS_H
namespace Eigen {
/** \internal
*
* \class TensorDimensions
* \ingroup CXX11_Tensor_Module
*
* \brief Set of classes used to encode and store the dimensions of a Tensor.
*
* The Sizes class encodes as part of the type the number of dimensions and the
* sizes corresponding to each dimension. It uses no storage space since it is
* entirely known at compile time.
* The DSizes class is its dynamic sibling: the number of dimensions is known
* at compile time but the sizes are set during execution.
*
* \sa Tensor
*/
// Boiler plate code
namespace internal {
template<std::size_t n, typename Dimension> struct dget {
static const std::size_t value = get<n, typename Dimension::Base>::value;
};
template<typename Index, std::size_t NumIndices, std::size_t n, bool RowMajor>
struct fixed_size_tensor_index_linearization_helper
{
template <typename Dimensions> EIGEN_DEVICE_FUNC
static inline Index run(array<Index, NumIndices> const& indices,
const Dimensions& dimensions)
{
return array_get<RowMajor ? n : (NumIndices - n - 1)>(indices) +
dget<RowMajor ? n : (NumIndices - n - 1), Dimensions>::value *
fixed_size_tensor_index_linearization_helper<Index, NumIndices, n - 1, RowMajor>::run(indices, dimensions);
}
};
template<typename Index, std::size_t NumIndices, bool RowMajor>
struct fixed_size_tensor_index_linearization_helper<Index, NumIndices, 0, RowMajor>
{
template <typename Dimensions> EIGEN_DEVICE_FUNC
static inline Index run(array<Index, NumIndices> const& indices,
const Dimensions&)
{
return array_get<RowMajor ? 0 : NumIndices - 1>(indices);
}
};
} // end namespace internal
// Fixed size
#ifndef EIGEN_EMULATE_CXX11_META_H
template <typename std::size_t... Indices>
struct Sizes : internal::numeric_list<std::size_t, Indices...> {
typedef internal::numeric_list<std::size_t, Indices...> Base;
static const std::size_t total_size = internal::arg_prod(Indices...);
static EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE std::size_t TotalSize() {
return internal::arg_prod(Indices...);
}
Sizes() { }
template <typename DenseIndex>
explicit Sizes(const array<DenseIndex, Base::count>& /*indices*/) {
// todo: add assertion
}
#ifdef EIGEN_HAS_VARIADIC_TEMPLATES
explicit Sizes(std::initializer_list<std::size_t> /*l*/) {
// todo: add assertion
}
#endif
template <typename T> Sizes& operator = (const T& /*other*/) {
// add assertion failure if the size of other is different
return *this;
}
template <typename DenseIndex> EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE
size_t IndexOfColMajor(const array<DenseIndex, Base::count>& indices) const {
return internal::fixed_size_tensor_index_linearization_helper<DenseIndex, Base::count, Base::count - 1, false>::run(indices, *static_cast<const Base*>(this));
}
template <typename DenseIndex> EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE
size_t IndexOfRowMajor(const array<DenseIndex, Base::count>& indices) const {
return internal::fixed_size_tensor_index_linearization_helper<DenseIndex, Base::count, Base::count - 1, true>::run(indices, *static_cast<const Base*>(this));
}
};
#else
template <std::size_t n>
struct non_zero_size {
typedef internal::type2val<std::size_t, n> type;
};
template <>
struct non_zero_size<0> {
typedef internal::null_type type;
};
template <std::size_t V1=0, std::size_t V2=0, std::size_t V3=0, std::size_t V4=0, std::size_t V5=0> struct Sizes {
typedef typename internal::make_type_list<typename non_zero_size<V1>::type, typename non_zero_size<V2>::type, typename non_zero_size<V3>::type, typename non_zero_size<V4>::type, typename non_zero_size<V5>::type >::type Base;
static const size_t count = Base::count;
static const std::size_t total_size = internal::arg_prod<Base>::value;
static EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE size_t TotalSize() {
return internal::arg_prod<Base>::value;
}
Sizes() { }
template <typename DenseIndex>
explicit Sizes(const array<DenseIndex, Base::count>& indices) {
// todo: add assertion
}
#ifdef EIGEN_HAS_VARIADIC_TEMPLATES
explicit Sizes(std::initializer_list<std::size_t> l) {
// todo: add assertion
}
#endif
template <typename T> Sizes& operator = (const T& other) {
// to do: check the size of other
return *this;
}
template <typename DenseIndex> EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE
size_t IndexOfColMajor(const array<DenseIndex, Base::count>& indices) const {
return internal::fixed_size_tensor_index_linearization_helper<DenseIndex, Base::count, Base::count - 1, false>::run(indices, *this);
}
template <typename DenseIndex> EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE
size_t IndexOfRowMajor(const array<DenseIndex, Base::count>& indices) const {
return internal::fixed_size_tensor_index_linearization_helper<DenseIndex, Base::count, Base::count - 1, true>::run(indices, *this);
}
};
#endif
// Boiler plate
namespace internal {
template<typename Index, std::size_t NumIndices, std::size_t n, bool RowMajor>
struct tensor_index_linearization_helper
{
static EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE
Index run(array<Index, NumIndices> const& indices, array<Index, NumIndices> const& dimensions)
{
return array_get<RowMajor ? n : (NumIndices - n - 1)>(indices) +
array_get<RowMajor ? n : (NumIndices - n - 1)>(dimensions) *
tensor_index_linearization_helper<Index, NumIndices, n - 1, RowMajor>::run(indices, dimensions);
}
};
template<typename Index, std::size_t NumIndices, bool RowMajor>
struct tensor_index_linearization_helper<Index, NumIndices, 0, RowMajor>
{
static EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE
Index run(array<Index, NumIndices> const& indices, array<Index, NumIndices> const&)
{
return array_get<RowMajor ? 0 : NumIndices - 1>(indices);
}
};
} // end namespace internal
// Dynamic size
template <typename DenseIndex, std::size_t NumDims>
struct DSizes : array<DenseIndex, NumDims> {
typedef array<DenseIndex, NumDims> Base;
static const std::size_t count = NumDims;
EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE size_t TotalSize() const {
return internal::array_prod(*static_cast<const Base*>(this));
}
EIGEN_DEVICE_FUNC DSizes() {
for (int i = 0 ; i < NumDims; ++i) {
(*this)[i] = 0;
}
}
EIGEN_DEVICE_FUNC explicit DSizes(const array<DenseIndex, NumDims>& a) : Base(a) { }
DSizes& operator = (const array<DenseIndex, NumDims>& other) {
*static_cast<Base*>(this) = other;
return *this;
}
// A constexpr would be so much better here
EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE size_t IndexOfColMajor(const array<DenseIndex, NumDims>& indices) const {
return internal::tensor_index_linearization_helper<DenseIndex, NumDims, NumDims - 1, false>::run(indices, *static_cast<const Base*>(this));
}
EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE size_t IndexOfRowMajor(const array<DenseIndex, NumDims>& indices) const {
return internal::tensor_index_linearization_helper<DenseIndex, NumDims, NumDims - 1, true>::run(indices, *static_cast<const Base*>(this));
}
};
namespace internal {
template <typename DenseIndex, std::size_t NumDims> struct array_size<const DSizes<DenseIndex, NumDims> > {
static const size_t value = NumDims;
};
template <typename DenseIndex, std::size_t NumDims> struct array_size<DSizes<DenseIndex, NumDims> > {
static const size_t value = NumDims;
};
#ifndef EIGEN_EMULATE_CXX11_META_H
template <typename std::size_t... Indices> struct array_size<const Sizes<Indices...> > {
static const size_t value = Sizes<Indices...>::count;
};
template <typename std::size_t... Indices> struct array_size<Sizes<Indices...> > {
static const size_t value = Sizes<Indices...>::count;
};
#else
template <std::size_t V1, std::size_t V2, std::size_t V3, std::size_t V4, std::size_t V5> struct array_size<const Sizes<V1,V2,V3,V4,V5> > {
static const size_t value = Sizes<V1,V2,V3,V4,V5>::count;
};
template <std::size_t V1, std::size_t V2, std::size_t V3, std::size_t V4, std::size_t V5> struct array_size<Sizes<V1,V2,V3,V4,V5> > {
static const size_t value = Sizes<V1,V2,V3,V4,V5>::count;
};
template <std::size_t n, std::size_t V1, std::size_t V2, std::size_t V3, std::size_t V4, std::size_t V5> EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE std::size_t array_get(const Sizes<V1,V2,V3,V4,V5>& a) {
return get<n, typename Sizes<V1,V2,V3,V4,V5>::Base>::value;
};
#endif
template <typename Dims1, typename Dims2, size_t n>
struct sizes_match_up_to_dim {
static inline bool run(Dims1& dims1, Dims2& dims2) {
return (array_get<n>(dims1) == array_get<n>(dims2)) &
sizes_match_up_to_dim<Dims1, Dims2, n-1>::run(dims1, dims2);
}
};
template <typename Dims1, typename Dims2>
struct sizes_match_up_to_dim<Dims1, Dims2, 0> {
static inline bool run(Dims1& dims1, Dims2& dims2) {
return (array_get<0>(dims1) == array_get<0>(dims2));
}
};
template <typename Dims1, typename Dims2>
bool dimensions_match(Dims1& dims1, Dims2& dims2) {
if (array_size<Dims1>::value != array_size<Dims2>::value) {
return false;
}
return sizes_match_up_to_dim<Dims1, Dims2, array_size<Dims1>::value-1>::run(dims1, dims2);
}
} // end namespace internal
} // end namespace Eigen
#endif // EIGEN_CXX11_TENSOR_TENSOR_DIMENSIONS_H