blackman.hpp

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#pragma once
 
#include "common.hpp"
#include <sycl/sycl.hpp>
 
namespace dpnp::extensions::window::kernels
{
 
template <typename T>
class BlackmanFunctor
{
private:
    T *data = nullptr;
    const std::size_t N;
 
public:
    BlackmanFunctor(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 = T(2) * i / (N - 1);
        data[i] = T(0.42) - T(0.5) * sycl::cospi(alpha) +
                  T(0.08) * sycl::cospi(T(2) * alpha);
    }
};
 
template <typename fnT, typename T>
struct BlackmanFactory
{
    fnT get()
    {
        if constexpr (std::is_floating_point_v<T>) {
            return window_impl<T, BlackmanFunctor>;
        }
        else {
            return nullptr;
        }
    }
};
 
} // namespace dpnp::extensions::window::kernels