On 6 May 2018, at 23:00, boB Stepp <robertvst...@gmail.com> wrote:
>I was solving a programming problem in one of my books concerning the >generation of a Collatz sequence >(https://en.wikipedia.org/wiki/Collatz_conjecture), and started to >wonder how I should separate my program's output from its logic. It >seems like this should be obvious to me, but, unfortunately, it isn't. >The core functions from my program are: >#---------------------------------------------------------------------------- >def collatz(integer): > """Returns the Collatz sequence number corresponding to integer. integer > must be > 0, or the sequence will not converge to 1.""" > if integer % 2 == 0: > return integer // 2 > else: > return 3 * integer + 1 >def generate_collatz_sequence(seed): > """Generates a Collatz sequence starting from seed. > seed must be a positive integer, or the sequence will not > coverge to 1.""" > counter = 0 > collatz_number = seed > print("Collatz seed number: ", collatz_number) > while True: > counter += 1 > collatz_number = collatz(collatz_number) > print("Collatz number", counter, ": ", collatz_number) > if collatz_number == 1: > print("The Collatz sequence has once again converged to 1!") > break >#---------------------------------------------------------------------------- >My understanding of best practice here is that I should not have any >print() calls inside my generate_collatz_sequence() function. I >_could_ store the generated sequence in a list and return it, but that >does not seem like good use of RAM if some user-supplied seed value >led to kazillions of Collatz sequence numbers being generated. The clue is in that last word. Write a generator function that yields the intermediate results. Alan g. _______________________________________________ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: https://mail.python.org/mailman/listinfo/tutor
