Eigen::indexing Namespace Reference

Functions
template<int N>
static const auto	fix ()
template<typename SizeType, typename IncrType>
auto	lastN (SizeType size, IncrType incr) -> decltype(seqN(Eigen::placeholders::last -(size - fix< 1 >()) *incr, size, incr))
template<typename FirstType, typename LastType, typename IncrType>
auto	seq (FirstType f, LastType l, IncrType incr)
template<typename FirstType, typename SizeType, typename IncrType>
ArithmeticSequence< typename internal::cleanup_index_type< FirstType >::type, typename internal::cleanup_index_type< SizeType >::type, typename internal::cleanup_seq_incr< IncrType >::type >	seqN (FirstType first, SizeType size, IncrType incr)

Variables
static constexpr Eigen::internal::all_t	all
static constexpr const last_t	last
static constexpr auto	lastp1

Detailed Description

The sole purpose of this namespace is to be able to import all functions and symbols that are expected to be used within operator() for indexing and slicing. If you already imported the whole Eigen namespace:

using namespace Eigen; 

then you are already all set. Otherwise, if you don't want/cannot import the whole Eigen namespace, the following line:

using namespace Eigen::indexing; 

is equivalent to:

using Eigen::fix;
using Eigen::seq;
using Eigen::seqN;
using Eigen::placeholders::all;
using Eigen::placeholders::last;
using Eigen::placeholders::lastN;  // c++11 only
using Eigen::placeholders::lastp1;

Function Documentation

fix()

template<int N>

static const auto Eigen::fix ( )

static

This identifier permits to construct an object embedding a compile-time integer N.

Template Parameters

N	the compile-time integer value

It is typically used in conjunction with the Eigen::seq and Eigen::seqN functions to pass compile-time values to them:

seqN(10,fix<4>,fix<-3>)   // <=> [10 7 4 1] 

See also the function fix(int) to pass both a compile-time and runtime value.

In c++14, it is implemented as:

template<int N> static const internal::FixedInt<N> fix{};

where internal::FixedInt<N> is an internal template class similar to std::integral_constant <int,N> Here, fix<N> is thus an object of type internal::FixedInt<N>.

See also

fix<N>(int), seq, seqN

lastN()

template<typename SizeType, typename IncrType>

auto Eigen::placeholders::lastN	(	SizeType	size,
		IncrType	incr ) -> decltype(seqN(Eigen::placeholders::last - (size - fix<1>()) * incr, size, incr))

[c++11]

Returns

a symbolic ArithmeticSequence representing the last size elements with increment incr.

It is a shortcut for:

seqN(last-(size-fix<1>)*incr, size, incr) 

See also

lastN(SizeType), seqN(FirstType,SizeType), seq(FirstType,LastType,IncrType)

seq()

template<typename FirstType, typename LastType, typename IncrType>

auto Eigen::seq	(	FirstType	f,
		LastType	l,
		IncrType	incr )

Returns

an ArithmeticSequence starting at f, up (or down) to l, and with positive (or negative) increment incr

It is essentially an alias to:

seqN(f, (l-f+incr)/incr, incr);

See also

seqN(FirstType,SizeType,IncrType), seq(FirstType,LastType)

seqN()

template<typename FirstType, typename SizeType, typename IncrType>

ArithmeticSequence< typename internal::cleanup_index_type< FirstType >::type, typename internal::cleanup_index_type< SizeType >::type, typename internal::cleanup_seq_incr< IncrType >::type > Eigen::seqN	(	FirstType	first,
		SizeType	size,
		IncrType	incr )

Returns

an ArithmeticSequence starting at first, of length size, and increment incr

See also

seqN(FirstType,SizeType), seq(FirstType,LastType,IncrType)

Variable Documentation

all

Eigen::internal::all_t Eigen::placeholders::all

staticconstexpr

Can be used as a parameter to DenseBase::operator()(const RowIndices&, const ColIndices&) to index all rows or columns

last

const last_t Eigen::placeholders::last

staticconstexpr

Can be used as a parameter to Eigen::seq and Eigen::seqN functions to symbolically reference the last element/row/columns of the underlying vector or matrix once passed to DenseBase::operator()(const RowIndices&, const ColIndices&).

This symbolic placeholder supports standard arithmetic operations.

A typical usage example would be:

using namespace Eigen;
using Eigen::placeholders::last;
VectorXd v(n);
v(seq(2,last-2)).setOnes();

See also

end

lastp1

auto Eigen::placeholders::lastp1

staticconstexpr

Can be used as a parameter to Eigen::seq and Eigen::seqN functions to symbolically reference the last+1 element/row/columns of the underlying vector or matrix once passed to DenseBase::operator()(const RowIndices&, const ColIndices&).

This symbolic placeholder supports standard arithmetic operations. It is essentially an alias to last+fix<1>.

See also

last