Function parallel_matrix_rows 

pub fn parallel_matrix_rows<T, U, F>(matrix: &[&[T]], op: F) -> Vec<U>
where
    T: Sync,
    U: Send,
    F: Fn(&[T]) -> U + Sync,

Parallel matrix row operations

Applies an operation to each row of a matrix represented as a slice of slices. Useful for BLAS-like operations on matrices.