Python列表中去重的多种方法，,怎么快速的对列表进行

怎么快速的对列表进行去重呢，去重之后原来的顺序会不会改变呢？

去重之后顺序会改变

set去重

列表去重改变原列表的顺序了

l1 = [1,4,4,2,3,4,5,6,1]l2 = list(set(l1))print(l2)    # [1, 2, 3, 4, 5, 6]

但是，可以通过列表中索引（index）的方法保证去重后的顺序不变。

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.groupby

import itertoolsl1 = [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())# 解决顺序问题t.sort(key=l1.index)print(t)         # [1, 4, 2, 3, 5, 6]

通过删除索引

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)]# 解决顺序问题t.sort(key=l1.index)print(t)    # [1, 4, 2, 3, 5, 6]

去重不改变顺序

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 reducel1 = [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]

Python列表中去重的多种方法