Most efficient option for build 3D structures using Eigen matrices

Question

I need a 3D matrix/array structure on my code, and right now I\'m relying on Eigen for both my matrices and vectors.

Right now I am creating a 3D structure using

Answer 1

A solution I used is to form a fat matrix containing all the matrices you need stacked.

MatrixXd A(60*60,60);

and then access them with block operations

A0 = A.block<60,60>(0*60,0);
...
A5 = A.block<60,60>(5*60,0);