use nalgebra::{matrix, stack}; fn main() { // Use multi-letter names for checking that the reported span comes out correctly let a11 = matrix![1, 2; 3, 4]; let a12 = matrix![5, 6; 7, 8]; let a21 = matrix![9, 10, 11]; let a22 = matrix![12, 13]; stack![a11, a12; a21, a22]; }