怎么快速的對列表進行去重呢，去重之后原來的順序會不會改變呢？

去重之后順序會改變

set去重

列表去重改變原列表的順序了l1 = [1,4,4,2,3,4,5,6,1]

l2 = list(set(l1))

print(l2) # [1, 2, 3, 4, 5, 6]

但是，可以通過列表中索引(index)的方法保證去重后的順序不變。l1 = [1,4,4,2,3,4,5,6,1]

l2 = list(set(l1))

l2.sort(key=l1.index)

print(l2) # [1, 4, 2, 3, 5, 6]

itertools.groupby

itertools.groupbyimport itertools

l1 = [1,4,4,2,3,4,5,6,1]

l1.sort()

l = []

it = itertools.groupby(l1)

for k,g in it:

l.append(k)

print(l) # [1, 2, 3, 4, 5, 6]

fromkeys l1 = [1,4,4,2,3,4,5,6,1]

t = list({}.fromkeys(l1).keys())

# 解決順序問題

t.sort(key=l1.index)

print(t) # [1, 4, 2, 3, 5, 6]

通過刪除索引l1 = [1,4,4,2,3,4,5,6,1]

t = l1[:]

for i in l1:

while t.count(i) >1:

del t[t.index(i)]

# 解決順序問題

t.sort(key=l1.index)

print(t) # [1, 4, 2, 3, 5, 6]

去重不改變順序

建立新列表[]l1 = [1,4,4,2,3,4,5,6,1]

new_l1 = []

for i in l1:

if i not in new_l1:

new_l1.append(i)

print(new_l1) # [1, 4, 2, 3, 5, 6]

reduce方法from functools import reduce

l1 = [1,4,4,2,3,4,5,6,1]

func = lambda x,y:x if y in x else x + [y]

print(reduce(func,[[],]+l1)) # [1, 4, 2, 3, 5, 6]

https://www.cnblogs.com/xxpythonxx/p/12181224.html