Hi, I'm using ArrayXd in my code and I found the resize() function didn't what I think it should do. For simplicity, I'm showing this problem with the following code.

Code: Select all

#include <iostream>
#include <eigen3/Eigen/Core>
int main(int argc, char** argv)
{
        Eigen::ArrayXd arr;
        arr.resize(3,4);
        std::cout<<"rows="<<arr.rows()<<"\ncols="<<arr.cols()<<std::endl;
        return 0;
}


The output was

Code: Select all

rows=3
cols=1


I would expect "cols=4" however. If I use MatrixXd instead of ArrayXd, cols() will return 4. My understanding is that Matrix and Array should behave the same here, but no. Is it designed to be like this or a bug?

Well, solved the problem. ArrayXd is not the array version of MatrixXd, but the array version of VectorXd. The array version of MatrixXd is ArrayXXd.
VectorXd -> ArrayXd
MatrixXd -> ArrayXXd