Integra.cpp

#include <iostream>
#include <experimental/simd>
int main() {
    int n = 24;
    double* A = new double(n*n);
    
    using Type = std::experimental::fixed_size_simd<double, 2>;
    constexpr std::size_t K = 2;
    for (int i = 1; i < n;i++) {
        for (int j = 0; j < i;j++) {
            Type norm(0), pro(0);// norm1(0), pro1(0);
            for (int k = 0; k < n;k+=K) {
                // store previous Gram-Schmidt in A
                Type va(&A[j * n + k], std::experimental::element_aligned);
                Type vb(&A[i * n + k], std::experimental::element_aligned);

                //Type vc(&A[j * n + k + 2], std::experimental::element_aligned);
                //Type vd(&A[i * n + k + 2], std::experimental::element_aligned);

                // Type ve(&A[j * n + k + 4], std::experimental::element_aligned);
                // Type vf(&A[i * n + k + 4], std::experimental::element_aligned);

                // Type vg(&A[j * n + k + 6], std::experimental::element_aligned);
                // Type vh(&A[i * n + k + 6], std::experimental::element_aligned);

                norm += va * va;
                pro += va * vb;

                //norm += vc * vc;
                //pro += vc * vd;

                // norm += ve * ve;
                // pro += ve * vf;

                // norm += vg * vg;
                // pro += vg * vh;
                //norm += A[i * n + k] * A[i * n + k];
                //in_pro += A[j * n + k] * A[i * n + k];
            }
            //double coef = (std::experimental::reduce(pro) + std::experimental::reduce(pro1)) / 
            //     (std::experimental::reduce(norm) + std::experimental::reduce(norm1));
            double coef = (std::experimental::reduce(pro)) / 
                 (std::experimental::reduce(norm));
            for (int k = 0;k < n;k+=K) {
                //A[i * n + k] -= coef * A[j * n + k];
                Type vi(&A[i * n + k], std::experimental::element_aligned);
                Type vj(&A[j * n + k], std::experimental::element_aligned);
                vi -= coef * vj;
                vi.copy_to(&A[i * n + k], std::experimental::element_aligned);
            }
        }
    }
    for (int i = 0; i <n;i++) {
        for (int j = i + 1; j < n;j++) {
            double pro= 0.0;
            for (int k = 0; k < n;k++) {
                pro += A[i * n + k] * A[j * n + k];
            }
            if (abs(pro) > 1e-12) {
                std::cout << pro << std::endl;
            }
        }
    }
   
}