Eigen sparse 基本操作：构造 & 输出

#include <iostream>#include "Eigen/Sparse"int main(){Eigen::SparseMatrix<float> m(3, 3);std::vector<Eigen::Triplet<float> > triple;for (int i = 0; i < 3; i++) {for (int j = 0; j < 3; j++) {triple.push_back(Eigen::Triplet<float>(i, j, 0.1));}}triple.push_back(Eigen::Triplet<float>(1, 1, 0.1));////相同下标重复插入，则表示相加m.setFromTriplets(triple.begin(), triple.end());//std::cout << m << std::endl; //直接这样输出也是可以的for (int k = 0; k < m.outerSize(); ++k) {for (Eigen::SparseMatrix<float>::InnerIterator it(m, k); it; ++it){//std::cout << it.row() << " " << it.col() << " : " << it.value() << std::endl;std::cout << it.value() << " ";}std::cout << std::endl;}return 0;}