norms.h

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#ifndef FUSED_ALGORITHMS_NORMS_H
#define FUSED_ALGORITHMS_NORMS_H
 
#include "config.h"
#include "fused/fused_matrix.h"
#include "fused/fused_vector.h"
#include "math/math_utils.h" // math::abs, math::sqrt
 
namespace matrix_algorithms
{
 
    template <typename T, my_size_t N>
    T norm1(const FusedMatrix<T, N, N> &A)
    {
        T max_col_sum = T(0);
 
        for (my_size_t j = 0; j < N; ++j)
        {
            T col_sum = T(0);
 
            for (my_size_t i = 0; i < N; ++i)
            {
                col_sum += math::abs(A(i, j));
            }
 
            if (col_sum > max_col_sum)
            {
                max_col_sum = col_sum;
            }
        }
 
        return max_col_sum;
    }
 
    template <typename T, my_size_t N>
    T norm2(const FusedVector<T, N> &v)
    {
        static_assert(is_floating_point_v<T>,
                      "norm2 requires a floating-point scalar type");
 
        T sum_sq = T(0);
 
        for (my_size_t i = 0; i < N; ++i)
        {
            sum_sq += v(i) * v(i);
        }
 
        return math::sqrt(sum_sq);
    }
 
} // namespace matrix_algorithms
 
#endif // FUSED_ALGORITHMS_NORMS_H