xmasked_view

Defined in xtensor/xmasked_view.hpp

template<class CTD, class CTM>
class xmasked_view : public xt::xview_semantic<xmasked_view<CTD, CTM>>, private xt::xaccessible<xmasked_view<CTD, CTM>>, private xt::xiterable<xmasked_view<CTD, CTM>>

View on an xoptional_assembly or xoptional_assembly_adaptor hiding values depending on a given mask.

The xmasked_view class implements a view on an xoptional_assembly or xoptional_assembly_adaptor, it takes this xoptional_assembly and a mask as input. The mask is an xexpression containing boolean values, whenever the value of the mask is false, the optional value of xmasked_view is considered missing, otherwise it depends on the underlying xoptional_assembly.

Template Parameters
  • CTD – The type of expression holding the values.

  • CTM – The type of expression holding the mask.

Constructors

template<class D, class M>
inline xmasked_view(D &&data, M &&mask)

Creates an xmasked_view, given the xoptional_assembly or xoptional_assembly_adaptor and the mask.

Parameters

Size and shape

inline size_type size() const noexcept

Returns the number of elements in the xmasked_view.

inline const inner_shape_type &shape() const noexcept

Returns the shape of the xmasked_view.

inline const inner_strides_type &strides() const noexcept

Returns the strides of the xmasked_view.

inline const inner_backstrides_type &backstrides() const noexcept

Returns the backstrides of the xmasked_view.

Data

template<class ...Args>
inline auto operator()(Args... args) -> reference

Returns a reference to the element at the specified position in the xmasked_view.

Parameters

args – a list of indices specifying the position in the xmasked_view. Indices must be unsigned integers, the number of indices should be equal or greater than the number of dimensions of the xmasked_view.

template<class ...Args>
inline auto operator()(Args... args) const -> const_reference

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

Parameters

args – a list of indices specifying the position in the xmasked_view. Indices must be unsigned integers, the number of indices should be equal or greater than the number of dimensions of the xmasked_view.

template<class ...Args>
inline auto unchecked(Args... args) -> reference

Returns a reference to the element at the specified position in the xmasked_view.

Warning

This method is meant for performance, for expressions with a dynamic number of dimensions (i.e. not known at compile time). Since it may have undefined behavior (see parameters), operator() should be prefered whenever it is possible.

Warning

This method is NOT compatible with broadcasting, meaning the following code has undefined behavior:

xt::xarray<double> a = {{0, 1}, {2, 3}};
xt::xarray<double> b = {0, 1};
auto fd = a + b;
double res = fd.uncheked(0, 1);

Parameters

args – a list of indices specifying the position in the xmasked_view. Indices must be unsigned integers, the number of indices must be equal to the number of dimensions of the xmasked_view, else the behavior is undefined.

template<class ...Args>
inline auto unchecked(Args... args) const -> const_reference

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

Warning

This method is meant for performance, for expressions with a dynamic number of dimensions (i.e. not known at compile time). Since it may have undefined behavior (see parameters), operator() should be prefered whenever it is possible.

Warning

This method is NOT compatible with broadcasting, meaning the following code has undefined behavior:

xt::xarray<double> a = {{0, 1}, {2, 3}};
xt::xarray<double> b = {0, 1};
auto fd = a + b;
double res = fd.uncheked(0, 1);

Parameters

args – a list of indices specifying the position in the xmasked_view. Indices must be unsigned integers, the number of indices must be equal to the number of dimensions of the xmasked_view, else the behavior is undefined.

template<class It>
inline auto element(It first, It last) -> reference

Returns a reference to the element at the specified position in the xmasked_view.

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 xmasked_view.

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

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

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 xmasked_view.

Public Functions

inline layout_type layout() const noexcept

Return the layout_type of the xmasked_view.

Returns

layout_type of the xmasked_view

template<class T>
inline void fill(const T &value)

Fills the data with the given value.

Parameters

value – the value to fill the data with.

inline data_type &value() noexcept

Return an expression for the values of the xmasked_view.

inline const data_type &value() const noexcept

Return a constant expression for the values of the xmasked_view.

inline mask_type &visible() noexcept

Return an expression for the mask of the xmasked_view.

inline const mask_type &visible() const noexcept

Return a constant expression for the mask of the xmasked_view.