无聊的日记

第1章 2026年7月28日

今日回看之前写的生命游戏实现:

(define conway-kernel
  (<< (Array #(1 1 1 1 0 1 1 1 1))
      (rho2 3 3)))
(define (neighbor grid)
  (<< conway-kernel
      (Convolve2 grid '(1 1))))
(define (step grid)
  (Materialize2
   ((Zip-with
     (λ (x n)
       (if (= x 1)
           (if (or (= n 2) (= n 3)) 1 0)
           (if (= n 3) 1 0))))
    grid (neighbor grid))))

(define kernel
  (array '(3 3) (const 1)))
(define (sum9 grid)
  (<< kernel (Convolve2 grid '(1 1))))
(define (step^ grid)
  (Materialize2
   ((Zip-with
     (λ (x n)
       (if (or (= n 3)
               (and (= x 1) (= n 4)))
           1 0)))
    grid (sum9 grid))))