#include “Eigen/Core” #include “Eigen/LU” Eigen::MatrixXd A(3,3); A << 1,1,1, 1,2,1, 1,2,3; cout <<"A = " << endl << A << endl; Eigen::VectorXd b(3); b << 5,3,8; cout <<"b = " << endl << b << endl; Eigen::VectorXd x = A.fullPivLu().solve(b); cout <<"x = " << endl << x << endl; 出力結果 A = 1 1 1 1 2 1 1 2 3 b = 5 3 8 x = 4.5 -2 2.5
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