Reshape.hpp

// TODO: Consider zero-copy reshape/flatten views once view support is implemented.
 
#pragma once
 
#include <algorithm>
 
#include <stratax/core/dtypes/Concepts.hpp>
#include <stratax/core/Shape.hpp>
#include <stratax/exceptions/Exceptions.hpp>
#include <stratax/containers/Tensor.hpp>
#include <stratax/containers/Vector.hpp>
 
namespace stratax::manipulation {
 
template<Array A>
[[nodiscard]]
stratax::container::Tensor<typename A::value_type>
reshape(const A& arr, const stratax::core::Shape& shape)
{
    const auto target_size = shape.elements();
    if (arr.size() != target_size)
    {
        throw Exceptions::ShapeError(
            "Reshape must preserve the number of elements.");
    }
 
    stratax::container::Tensor<typename A::value_type> result(shape);
    std::copy(arr.begin(), arr.end(), result.begin());
 
    return result;
}
 
template<Array A>
[[nodiscard]]
stratax::container::Vector<typename A::value_type>
flatten(const A& arr)
{
    stratax::container::Vector<typename A::value_type> result(arr.size());
    std::copy(arr.begin(), arr.end(), result.begin());
 
    return result;
}
 
} // namespace stratax::manipulation