bartlett.hpp

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#pragma once

#include "common.hpp"
#include <sycl/sycl.hpp>

namespace dpnp::extensions::window::kernels
{

template <typename T>
class BartlettFunctor
{
private:
    T *data = nullptr;
    const std::size_t N;

public:
    BartlettFunctor(T *data, const std::size_t N) : data(data), N(N) {}

    void operator()(sycl::id<1> id) const
    {
        const auto i = id.get(0);

        const T alpha = (N - 1) / T(2);
        data[i] = T(1) - sycl::fabs(i - alpha) / alpha;
    }
};

template <typename fnT, typename T>
struct BartlettFactory
{
    fnT get()
    {
        if constexpr (std::is_floating_point_v<T>) {
            return window_impl<T, BartlettFunctor>;
        }
        else {
            return nullptr;
        }
    }
};

} // namespace dpnp::extensions::window::kernels