On 18 Aug 2010, at 13:21 , Laurens Vets wrote: > On 8/12/2010 1:26 AM, Steven D'Aprano wrote: >> On Thu, 12 Aug 2010 07:04:15 am Laurens Vets wrote: >> >>> I need to generate a list of 30 numbers randomly chosen from 1, 2, 3, >>> 4, 5& 6. However, I cannot have more than 2 numbers which are the >>> same next to each other. I came up with the following (Please ignore >>> the fact that I'm trying to avoid an IndexError in a stupid way :)): >> >> I can't possible do that! :) >> >>> import random >>> reeks = [] >>> while len(reeks)<= 1: >>> number = random.randrange(1, 7, 1) >>> reeks.append(number) >>> >>> while len(reeks)<= 29: >>> nummer = random.randrange(1, 7, 1) >>> if nummer != reeks[-1] and nummer != reeks[-2]: >>> reeks.append(nummer) >>> print reeks >> >> This is probably a simpler way: >> >> import random >> reeks = [] >> for i in range(30): >> temp = [random.randint(1, 6)] >> while reeks[-2:-1] == reeks[-1:] == temp: >> # print "Triplet found:", reeks, temp >> temp = [random.randint(1, 6)] >> reeks.extend(temp) >> >> print reeks > > <snip> > > Thank you all for your help! I've added another condition to this program, > namely, in a range of 60, each 'random' number can only occur 10 times. I > came up with the following: > > import random > series = [] > for i in range(60): > temp = [random.randint(1, 6)] > while series[-2:-1] == series[-1:] == temp: > temp = [random.randint(1, 6)] > while series.count(temp[0]) >= 10: > temp = [random.randint(1, 6)] > series.extend(temp) > print series > > However, this also generates gems such as: > > [4, 4, 3, 6, 3, 2, 6, 3, 4, 3, 4, 1, 4, 2, 4, 3, 4, 4, 6, 2, 1, 5, 5, 6, 5, > 6, 5, 6, 3, 3, 1, 6, 6, 4, 1, 5, 2, 6, 6, 4, 2, 5, 3, 1, 5, 5, 2, 1, _2_, > _2_, _2_, 3, 3, 2, 1, 5, 1, 1, 5, 1] > > [1, 4, 3, 1, 5, 3, 5, 1, 5, 6, 5, 3, 2, 6, 1, 4, 1, 5, 5, 2, 6, 2, 4, 1, 3, > 1, 2, 1, 1, 3, 1, 6, 6, 3, 2, 3, 6, 4, 5, 6, 5, 6, 3, 6, 2, 4, 5, 3, 3, 4, 6, > _4_, _4_, _4_, 5, 4, _2_, _2_, _2_, _2_] > > I thought this needed to become the following: > > import random > series = [] > for i in range(60): > temp = [random.randint(1, 6)] > print "Temp", i, ":", temp > while series[-2:-1] == series[-1:] == series: > if series.count(temp[0]) >= 10: > temp = [random.randint(1, 6)] > series.extend(temp) > print series > > But this just hangs whenever the while clause matches. I'm not sure what I'm > doing wrong here. I do know the random.shuffle() function, but I can't put my > conditions in there.
I assume the '== series:' is a typo, and should be '== temp'. Otherwise I don't see how this matches, unless series = [] (which means the while clause always matches, right at the start. Perhaps that actually is what you're seeing?). That's probably the disadvantage of using a list to avoid an IndexError (sorry Steven; I would have just caught the IndexError, or have an 'if i < 2: continue' statement in there.) As suggestion for avoiding occurrences of > 10 times: use a dict, where the random numbers become the keys and you add +1 every time to d[temp]. Checking if d[temp] > 10 is then very easy. Cheers, Evert > > Any push in the right direction would be greatly appreciated :) > _______________________________________________ > Tutor maillist - Tutor@python.org > To unsubscribe or change subscription options: > http://mail.python.org/mailman/listinfo/tutor _______________________________________________ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
