Hello. This is my first question to Eigen forum.
I'm glad to meet you.

I have two questions.

1. How can I get reduced row echelon form of a matrix?
I couldn't find the way. Should I do it by myself?

2. I learned how to get rank of matrix with Eigen from stack-overflow
http://stackoverflow.com/questions/31041921/how-to-get-rank-of-a-matrix-in-eigen-library
But as for me, the Eigen's way of getting rank seems difficult.
Why Eigen doesn't have direct method or function which ,presumably, go like m.rank() or rank(m)?
I guess there are technical difficulties for implementing them.

Thank you.