python的列表(数组)无比强大,下面介绍集中去除列表中重复元素的方法,各有利弊,可根据需要选用
最简单的方法是使用集合set,这种方法会改变列表的原有顺序输出结果: ['a', 'c', 'b', 'd'] 还有一种据说速度更快的,没测试过两者的速度差别
- l1 = ['b','c','d','b','c','a','a']
- l2 = list(set(l1))
- print l2
输出结果: ['a', 'c', 'b', 'd'] 这两种都有个缺点,去除重复元素后排序变了: ['a', 'c', 'b', 'd'] 如果想要保持他们原来的排序: 用list类的sort方法
- l1 = ['b','c','d','b','c','a','a']
- l2 = {}.fromkeys(l1).keys()
- print l2
输出结果: ['b', 'c', 'd', 'a'] 也可以这样写
- l1 = ['b','c','d','b','c','a','a']
- l2 = list(set(l1))
- l2.sort(key=l1.index)
- print l2
输出结果: ['b', 'c', 'd', 'a'] 也可以用遍历
- l1 = ['b','c','d','b','c','a','a']
- l2 = sorted(set(l1),key=l1.index)
- print l2
上面的代码也可以这样写
- l1 = ['b','c','d','b','c','a','a']
- l2 = []
- for i in l1:
- if not i in l2:
- l2.append(i)
- print l2
输出结果: ['b', 'c', 'd', 'a']
- l1 = ['b','c','d','b','c','a','a']
- l2 = []
- [l2.append(i) for i in l1 if not i in l2]
- print l2
来源: http://www.phpxs.com/code/1004844/