我有一个名单列表,我想将其放入n个组中。我可以轻松地做到这一点。但是,我的问题是,无论如何,有些项目都无法组合在一起。有一个简单的解决方案吗?
我现在就是这样做的:
import random
name_list = ["Item1", "Item2", "Item3", "Item4", "Item5", "Item6", "Item7"]
n = 2
random.seed(4)
random.shuffle(name_list)
test = [name_list[i:i + n] for i in xrange(0, len(name_list), n)]
print(test)
因此,我会得到4组,随机洗牌,最后一组只有1组(没关系)。但是,我们要说Item1
和Item5
不能最终结合在一起。我该怎么做?
答案 0 :(得分:0)
这里我们为随机分发的项目获取组或“块”。
<强>鉴于强>
import random
import itertools as it
import more_itertools as mit
random.seed(4)
n = 2
name_list = ["Item1", "Item2", "Item3", "Item4", "Item5", "Item6", "Item7"]
blacklist = ["Item1", "Item5"]
<强>代码强>
def get_random_groups(lst, size=2, blacklist=None):
"""Return distributed items among `m` groups of lists."""
if blacklist is None:
blacklist = []
# Compute number of chunks
length = (len(lst))
if length % 2 == 0:
m = length//size
else:
m = (length+1)//size
# Edge cases
if len(blacklist) > m:
raise ValueError("Black-list is too long. Must be < number of chunks.")
if not set(blacklist).issubset(set(lst)):
raise ValueError("Black-list is not a subset of the main list.")
# Resize list
remnant_list = list(set(lst) - set(blacklist))
random.shuffle(remnant_list)
# Build chunks and distribute (blacklist first)
chunks = [list(c) for c in mit.distribute(m, blacklist)]
random.shuffle(chunks)
for chunk in chunks[:]:
while len(chunk) < size:
try:
chunk += [remnant_list.pop(-1)]
except IndexError:
return chunks
<强>演示强>
# Without blacklist
get_random_groups(name_list, size=n)
# Out: [['Item5', 'Item1'], ['Item3', 'Item6'], ['Item7', 'Item2'], ['Item4']]
# With blacklist
get_random_groups(name_list, size=n, blacklist=blacklist)
# [['Item2', 'Item6'], ['Item1', 'Item3'], ['Item5', 'Item7'], ['Item4']]
# Invalid blacklist
blacklist = "Item1 Item3 Item 5 Item6 Item7".split()
get_random_groups(name_list, size=n, blacklist=blacklist)
# ValueError: Blacklist is too long. Must be < number of chunks.
# Invalid blacklist
blacklist = "Item1 Item9".split()
get_random_groups(name_list, size=n, blacklist=blacklist)
# ValueError("Black-list is not a subset of the main list.")
<强>详情
blacklist
中的项目将首先在块之间分配。因此,必须从剩余元素列表(remnant_list
)中删除这些项目。more_itertools.distribute
是第三方工具,可在m
个数量的块中促进分块和分发项目。您可以选择实施自己的算法来完成这两项任务。size
,否则将随机补余项添加到混洗块中。这种双重洗牌确保物品随机放置。