【Ubuntu】安装eigen

1 apt方式：
sudo apt install libeigen3-dev
sudo cp -r /usr/local/include/eigen3/Eigen /usr/local/include 

2 源码安装：
地址：http://eigen.tuxfamily.org/index.php?title=Main_Page
版本3.4.0地址：https://gitlab.com/libeigen/eigen/-/releases/3.4.0
(1)安装
  cd eigen3文件夹
  mkdir build
  cd build
  cmake ..
  sudo make install
头文件默认安装在：/usr/local/include/eigen3/
(2)cp
sudo cp -r /usr/local/include/eigen3/Eigen /usr/local/include 

(3)测试

test.cpp

#include

#include

using namespace Eigen;

using namespace Eigen::internal;

using namespace Eigen::Architecture;

 using namespace std;

int main()

{

RowVectorXd vec1(3);

vec1<< 1,2,3;

cout << "vec1=\n" << vec1 << endl;

return 0;

}

g++ test.cpp -o test

./test

结果如下即可。

vec1=

1 2 3