Macro mat 

macro_rules! mat {
    ($([ $($x:expr),+ $(,)? ]),+ $(,)?) => { ... };
    ($cols:expr $(,)?) => { ... };
}

Ergonomic constructor for a Matrix from f64 column data.

Both forms build through Matrix::try_from_cols and unwrap the result, so a length mismatch panics with the same error shape as the underlying call.

Forms

• Literal columns: mat![[1.0, 2.0, 3.0], [4.0, 5.0, 6.0]] produces a 3-row, 2-column matrix.
• Slice-of-slices expression: mat!(&[&[1.0, 2.0, 3.0][..], &[4.0, 5.0, 6.0][..]]) produces the equivalent matrix from an existing &[&[f64]] value.

Example

use minarrow::mat;
let m = mat![[1.0, 2.0, 3.0], [4.0, 5.0, 6.0]];
assert_eq!((m.n_rows, m.n_cols), (3, 2));