nda::expr_call< F, As >

#include <nda/map.hpp>

Detailed Description

template<typename F, Array... As>
struct nda::expr_call< F, As >

A lazy function call expression on arrays/views.

The lazy expression call fulfils the nda::Array concept and can therefore be assigned to other nda::basic_array or nda::basic_array_view objects. For example:

nda::matrix<int> mat{{1, 2}, {3, 4}};
nda::matrix<int> pmat = nda::pow(mat, 2);

Here, nda::pow(mat, 2) returns a lazy expression call object which is then used in the constructor of pmat.

The callable object should take the array/view elements as arguments.

Template Parameters

F	Callable type.
As	nda::Array argument types.

Definition at line 83 of file map.hpp.

Public Member Functions
template<size_t I = 0>
auto &	operand ()
	Get one of the nda::Array arguments of the expression.
template<size_t I = 0>
auto const &	operand () const
	Const overload of expr_call::operand.
template<typename... Args>
auto	operator() (Args const &...args) const
	Function call operator.
template<typename Arg>
auto	operator[] (Arg const &arg) const
	Subscript operator.
auto	shape () const
	Get the shape of the nda::Array objects.
long	size () const
	Get the total size of the nda::Array objects.

Public Attributes
std::tuple< As... >	a
	Tuple containing the nda::Array arguments.
F	f
	Callable object of the expression.

Member Function Documentation

operand()

template<typename F, Array... As>

template<size_t I = 0>

auto & nda::expr_call< F, As >::operand ( )

inlinenodiscard

Get one of the nda::Array arguments of the expression.

The returned reference carries the constness of the expression object, i.e. a const expression never hands out a writable operand.

Template Parameters

I	Index of the argument in the tuple expr_call::a.

Returns

Reference to the I-th nda::Array argument.

Definition at line 175 of file map.hpp.

operator()()

template<typename F, Array... As>

template<typename... Args>

auto nda::expr_call< F, As >::operator() ( Args const &... args ) const

inline

Function call operator.

The arguments (usually multi-dimensional indices) are passed to all the nda::Array objects stored in the tuple and the results are then passed to the callable object.

If the arguments contain a range, a new lazy function call expression is returned.

Template Parameters

Args	Argument types.

Parameters

args	Function call arguments.

Returns

The result of the function call (depends on the callable and the arguments).

Definition at line 131 of file map.hpp.

operator[]()

template<typename F, Array... As>

template<typename Arg>

auto nda::expr_call< F, As >::operator[] ( Arg const & arg ) const

inline

Subscript operator.

The argument (usually a 1-dimensional index) is passed to all the nda::Array objects stored in the tuple and the results are then passed to the callable object.

If the argument is a range, a new lazy function call expression is returned.

Template Parameters

Arg	Argument types.

Parameters

arg	Subscript argument.

Returns

The result of the subscript operation (depends on the callable and the arguments).

Definition at line 148 of file map.hpp.

shape()

template<typename F, Array... As>

auto nda::expr_call< F, As >::shape ( ) const

inlinenodiscard

Get the shape of the nda::Array objects.

Returns

std::array<long, Rank> object specifying the shape of each nda::Array object.

Definition at line 157 of file map.hpp.

size()

template<typename F, Array... As>

long nda::expr_call< F, As >::size ( ) const

inlinenodiscard

Get the total size of the nda::Array objects.

Returns

Number of elements contained in each nda::Array object.

Definition at line 163 of file map.hpp.

Member Data Documentation

a

template<typename F, Array... As>

std::tuple<As...> nda::expr_call< F, As >::a

Tuple containing the nda::Array arguments.

Lvalue operands are stored by reference, so reading this member directly can hand out a writable operand even from a const expression. Access it through expr_call::operand instead, which propagates the constness of the expression object.

Definition at line 94 of file map.hpp.

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The documentation for this struct was generated from the following file:

• nda/map.hpp