xgenerator

Defined in xtensor/xgenerator.hpp

template <class F, class R, class S>
class xt::xgenerator

Multidimensional function operating on indices.

The xgenerator class implements a multidimensional function, generating a value from the supplied indices.

Template Parameters
  • F: the function type
  • R: the return type of the function
  • S: the shape type of the generator

Inherits from xt::xexpression< xgenerator< F, R, S > >, xt::xconst_iterable< xgenerator< F, R, S > >

Constructor

template <class Func>
xgenerator(Func &&f, const S &shape)

Constructs an xgenerator applying the specified function over the given shape.

Parameters
  • f: the function to apply
  • shape: the shape of the xgenerator

Size and shape

auto size() const

Returns the size of the expression.

auto dimension() const

Returns the number of dimensions of the function.

auto shape() const

Returns the shape of the xgenerator.

Data

template <class… Args>
auto operator()(Args... args) const

Returns the evaluated element at the specified position in the function.

Parameters
  • args: a list of indices specifying the position in the function. Indices must be unsigned integers, the number of indices should be equal or greater than the number of dimensions of the function.

template <class… Args>
auto at(Args... args) const

Returns a constant reference to the element at the specified position in the expression, after dimension and bounds checking.

Parameters
  • args: a list of indices specifying the position in the function. Indices must be unsigned integers, the number of indices should be equal to the number of dimensions of the expression.
Exceptions
  • std::out_of_range: if the number of argument is greater than the number of dimensions or if indices are out of bounds.

template <class It>
auto element(It first, It last) const

Returns a constant reference to the element at the specified position in the function.

Parameters
  • first: iterator starting the sequence of indices
  • last: iterator ending the sequence of indices The number of indices in the sequence should be equal to or greater than the number of dimensions of the container.

Broadcasting

template <class O>
bool broadcast_shape(O &shape) const

Broadcast the shape of the function to the specified parameter.

Return
a boolean indicating whether the broadcasting is trivial
Parameters
  • shape: the result shape

template <class O>
bool is_trivial_broadcast(const O&) const

Compares the specified strides with those of the container to see whether the broadcasting is trivial.

Return
a boolean indicating whether the broadcasting is trivial