Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > comp.lang.python > #4193

Re: Fibonacci series recursion error

Show all headers | View raw

Am 30.04.2011 09:43 schrieb harrismh777:

> On the other hand, I am very much interested in "yield," because of its
> obvious persistent state, On the other hand, I don't like you fib()
> function because it does not encapsulate the fib generator. I suppose
> you are considering whatever module is holding the fib() code as the
> encapsulation, but I thought the idea from the OP was to create a
> generator that could be called and return a list... this is a little goofy:
> list(islice(fib(), X))
>
> when what was wanted is:
>
> list = fib(X)

You can have both with the following:

def fib(max=None):
     a = b = 1
     while max is None or a <= max:
         yield a
         a, b = b, a+b
from itertools import islice
flist = list(islice(fib(), 100000))

flist2 = list(fib(100000))

or - if even the latter is unwanted -


def fibgen(max=None):
     a = b = 1
     while max is None or a <= max:
         yield a
         a, b = b, a+b

def fib(max=None, num=None):
     if num is None:
         return list(fibgen(max=max))
     else:
	from itertools import islice
	return list(islice(fib(max=max), num))


Thomas

Back to comp.lang.python | Previous | Next — Previous in thread | Next in thread | Find similar

Thread

Re: Fibonacci series recursion error harrismh777 <harrismh777@charter.net> - 2011-04-30 02:43 -0500
  Re: Fibonacci series recursion error Thomas Rachel <nutznetz-0c1b6768-bfa9-48d5-a470-7603bd3aa915@spamschutz.glglgl.de> - 2011-04-30 10:14 +0200
    Re: Fibonacci series recursion error harrismh777 <harrismh777@charter.net> - 2011-04-30 15:41 -0500
  Re: Fibonacci series recursion error Peter Otten <__peter__@web.de> - 2011-04-30 18:07 +0200
    Re: Fibonacci series recursion error harrismh777 <harrismh777@charter.net> - 2011-04-30 15:51 -0500

csiph-web