tannic::expression::Expansion< Source > Class Template Reference

Expression template for expanding (broadcasting) singleton dimensions of a tensor. More...

#include <views.hpp>

Public Member Functions
template<Integral... Sizes>
constexpr	Expansion (typename Trait< Source >::Reference source, Sizes... sizes)
	Construct an expansion view.
constexpr type	dtype () const
constexpr Shape const &	shape () const
constexpr Strides const &	strides () const
std::ptrdiff_t	offset () const
Tensor	forward () const

Detailed Description

template<Expression Source>
class tannic::expression::Expansion< Source >

Expression template for expanding (broadcasting) singleton dimensions of a tensor.

Template Parameters

Source

The expression or tensor type being expanded.

The Expansion view allows a tensor to be broadcast along dimensions where the original size is 1, enabling operations with larger tensors without copying data. Only dimensions with size 1 in the source tensor can be expanded; other dimensions must match the target shape.

Example:

Tensor X(float32, {1, 3});
auto Y = expand(X, 4, 3); // shape becomes (4, 3)

Constructor & Destructor Documentation

Expansion()

template<Expression Source>

template<Integral... Sizes>

constexpr tannic::expression::Expansion< Source >::Expansion ( typename Trait< Source >::Reference  source, Sizes...  sizes  )

inlineconstexpr

Construct an expansion view.

Stores reference to the source tensor and the requested target sizes.

Template Parameters

Sizes

Integral dimension sizes of the target shape.

Parameters

source	Reference to the source tensor or expression.
sizes	Dimension sizes for the expanded view.

Member Function Documentation

dtype()

template<Expression Source>

constexpr type tannic::expression::Expansion< Source >::dtype ( ) const

inlineconstexpr

Returns

The data type of the tensor elements.

Broadcasting does not change the element type, so the dtype is forwarded from the source tensor.

forward()

template<Expression Source>

Tensor tannic::expression::Expansion< Source >::forward

offset()

template<Expression Source>

std::ptrdiff_t tannic::expression::Expansion< Source >::offset ( ) const

inline

Returns

The byte offset of the expanded view from the start of the storage.

The offset is the same as the source tensor, because broadcasting does not change the underlying data location.

shape()

template<Expression Source>

constexpr Shape const & tannic::expression::Expansion< Source >::shape ( ) const

inlineconstexpr

Returns

The shape of the expanded view.

Calculation:

• Returns the requested target shape stored in the constructor.
• Validates that non-singleton dimensions of the source match the requested size.

Exceptions

Exception

if a non-singleton dimension in the source does not match the target.

strides()

template<Expression Source>

constexpr Strides const & tannic::expression::Expansion< Source >::strides ( ) const

inlineconstexpr

Returns

The strides of the expanded view.

Calculation:

• Copy the source strides.
• For each dimension where the source size is 1 and target size > 1, set stride to 0. This ensures the same memory element is repeated along expanded dimensions.

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The documentation for this class was generated from the following files:

• include/tannic/views.hpp
• include/tannic/tensor.hpp