#lang racket

(require racket/trace)

;; The Collatz conjecture

(define (collatz n)
  (if (= (modulo n 2) 0) (/ n 2)
      (+ 1 (* n 3))))


;; generate the series based on Collatz
(define (c-series n)
  (print n)
  (newline)
  (if (equal? n 1) 'done
      (let ((next (collatz n)))
	(c-series next))))

;; generate the series based on Collatz
(define (c-series2 n)
  (print n)
  (newline)
  (if (equal? n 1) 'done
      (c-series2 (collatz n))))






;; various numeric functions


(define examples
  '(
    (number? 1)
    (complex? 2+3i)
    (real? 3.14159)
    (real? +inf.0)
    (rational? 1)
    (integer? 1)
    (integer? +inf.0)
    (integer? 2.0)
    (exact-integer? 2.0)
    (exact-nonnegative-integer? 0)
    (exact-nonnegative-integer? -1)
    (exact-positive-integer? 0)
    (inexact-real? 3.4)
    (inexact-real? 3.5)
    (flonum? 3.4)
    (double-flonum? 3.4)
    (double-flonum? 3.4444444444)
    (single-flonum? 3.4)
    (zero? 0.0)
    (positive? 1)
    (negative? 1)
    (even? 1)
    (odd? 1)
    (exact? 3.14159)
    (inexact? 3.14159)
    (inexact->exact 3.14159)
    )
  )

(define (demo)
  (map
   (lambda (lst)
     (list (car lst)
	   (cadr lst)
	   '==>
	   (apply (eval (car lst)) (cdr lst))))
   examples))