Turn a list into a matrix

Matrify.swift

//: # Matrify
//:
//: Turn a list into a matrix

import Cocoa

let a = [1,2,3,4,5,6,7,8,9]

func matrify(list: [Int], rowLength: Int) -> [[Int]] {
    
    func iter(list: [Int], matrix: [[Int]]) -> [[Int]] {
        if list.count < rowLength {
            return matrix + [list]
        } else {
            return iter(Array(list[rowLength..<list.count]), matrix: matrix + [Array(list[0..<rowLength])])
        }
    }
    
    return iter(list, matrix: [])
}

matrify(a, rowLength: 4)