1

我想做的是,有一个字符列表,每个字符都是一个过程,然后我想从这个列表中随机选择(或伪随机,没关系),并执行该过程,然后我想要能够再次运行它,而不是获得相同的值,例如,如果我有五个值,我希望能够运行它 5 次,那么我第 6 次运行它,它什么也不返回。这是代码:

from Tkinter import*
from random import randint
Characters=[Percy,Annabeth,Leo,Chuck,Sarah]
Used = []
def callback():
    end = len(Characters)-1
    rando = randint(0,end)
    Characters[rando]
    for i in Characters:
         if Characters[rando] in Used:
            print 'This has already been used'
         else:
            Characters[rando]()
            Used.append(Characters[rando])
            break


game = Tk()
game.geometry('50x50+700+100')
Button1 = Button(game,text = '1',command =lambda:callback() )
Button1.pack(side=LEFT)


game.mainloop() 

我想得到

callback()

要正常运行,我已经尝试过您所看到的,但我也尝试过

if Characters[rando] in Used:
    print 'This has already been used'
else: 
   Characters[rando]
   Used.append(Characters[rando])

在这两种情况下,它都会多次运行相同的程序,例如,“Leo”可能会连续执行 3 次。我花了几个小时寻找一种方法来做到这一点,但我找不到。

4

2 回答 2

7

首先,我shuffleCharacters

Characters = [Percy,Annabeth,Leo,Chuck,Sarah]
random.shuffle(Characters)

现在,当您运行回调时,您会pop输出一个字符:

def callback():
    try:
       C = Characters.pop()  #popping the last one is more efficient than the first.
    except IndexError:
       return None

    return C()

由于这会破坏Characters,因此如果需要,您可能需要保留它的副本以重置:

 random.shuffle(Characters)
 Characters_save = Characters[:]

 def reset_characters():
     Characters[:] = Characters_save[:]
于 2012-10-22T18:45:42.640 回答
0

完全未经测试 - 但您可以实现一个基本类:

from random import shuffle

class CallNext(object):
    def __init__(self, vals):
        self.vals = vals[:]
        shuffle(self.vals)
        self.iter = iter(self.vals)
    def __call__(self):
        try:
            next(self.iter)()
        except StopIteration as e:
            pass # or do something smarter?

另一个代替捕获的选择StopIteration是使用:

next(self.iter, lambda: None)()

然后有:

Button1 = Button(game, text='1', command=CallNext(Characters) )
于 2012-10-22T19:10:59.553 回答