‘Vector’ in namespace ‘Eigen’ does not name a template type; did you mean ‘VectorXd’?

[YuanwenFu]

Ubuntu18.04
When I execute the following command,

mkdir build
cd build
cmake ..
make

something went wrong. The error information is as follows.

In file included from /home/fyw/similarity-transformation/similarity-transformation-main/tests/test.cc:2:
/home/fyw/similarity-transformation/similarity-transformation-main/similarity_transformation.h:12:23: error: ‘Vector’ in namespace ‘Eigen’ does not name a template type; did you mean ‘VectorXd’?
   12 |   using VecN = Eigen::Vector<double, DimN>;
      |                       ^~~~~~
      |                       VectorXd
/home/fyw/similarity-transformation/similarity-transformation-main/similarity_transformation.h:13:23: error: ‘Vector’ in namespace ‘Eigen’ does not name a template type; did you mean ‘VectorXd’?
   13 |   using VecM = Eigen::Vector<double, DimM>;
      |                       ^~~~~~
      |                       VectorXd
/home/fyw/similarity-transformation/similarity-transformation-main/similarity_transformation.h:49:27: error: ‘VecN’ does not name a type; did you mean ‘Vec3’?
   49 |     State operator+(const VecN& rhs) const {
      |                           ^~~~
      |                           Vec3

[YuanwenFu]

I changed the code from

  using VecN = Eigen::Vector<double, DimN>;
  using VecM = Eigen::Vector<double, DimM>;

to

  using VecN = Eigen::Matrix<double, DimN, 1>;
  using VecM = Eigen::Matrix<double, DimM, 1>;

Then the make instruction executes successfully!