Python3 列表(List)基础
2021-06-22 11:06
标签：rem 智能 人工 app 南京 函数 family size 重庆 打印输出结果： 打印输出结果： 打印输出结果： 打印输出结果： 向列表中插入数据。 打印输出结果： 将一条数据从列表中移除。 打印输出结果： 打印输出结果： 打印输出结果： 用于移除列表中的一个元素（默认最后一个元素），并且返回该元素的值。 打印输出结果： 用于从列表中找出某个值第一个匹配项的索引位置。 打印输出结果：3 用于统计字符串里某个字符出现的次数。 打印输出结果：3 用于反向列表中元素。 打印输出结果： 用于对原列表进行排序，如果指定参数，则使用比较函数指定的比较函数。 list_r = ["A","B","C","x","a"] 打印输出结果： 用于在列表末尾一次性追加另一个序列中的多个值（用新列表扩展原来的列表）。 输出打印结果： 计算列表元素个数。 打印输出结果： Python3 列表(List)基础 标签：rem 智能 人工 app 南京 函数 family size 重庆 原文地址：https://www.cnblogs.com/bad-robot/p/9678699.html1、初始化
cities = ["北京","上海",["深圳","广州"],"杭州"]
jobs = []
jobs.append("人工智能")
jobs.append("后端开发")
jobs.append("前端开发")
jobs.append("数据分析")
print(cities)
print(jobs)
[‘北京‘, ‘上海‘, [‘深圳‘, ‘广州‘], ‘杭州‘]
[‘人工智能‘, ‘后端开发‘, ‘前端开发‘, ‘数据分析‘]
2、切片
print(cities[0:-1:2])
[‘北京‘, [‘深圳‘, ‘广州‘]]
print(cities[::2])
[‘北京‘, [‘深圳‘, ‘广州‘]]
print(cities[:])
[‘北京‘, ‘上海‘, [‘深圳‘, ‘广州‘], ‘杭州‘]
3、方法
3.1、insert()
cities = ["北京","上海",["深圳","广州"],"杭州"]
cities.insert(1,"天津")
print(cities)
[‘北京‘, ‘天津‘, ‘上海‘, [‘深圳‘, ‘广州‘], ‘杭州‘]
3.2、remove()
cities = ["北京","上海",["深圳","广州"],"杭州"]
cities.remove("上海")
print(cities)
[‘北京‘, [‘深圳‘, ‘广州‘], ‘杭州‘]
3.3、del
3.3.1、删除列表中的元素
cities = ["北京","上海",["深圳","广州"],"杭州"]
del cities[1]
print(cities)
[‘北京‘, [‘深圳‘, ‘广州‘], ‘杭州‘]
3.3.2、删除列表
new_cities = ["武汉","成都","重庆","南京"]
del new_cities
print(new_cities)
NameError: name ‘new_cities‘ is not defined
3.4、pop()
cities = ["北京","上海",["深圳","广州"],"杭州"]
cities.pop(1)
print(cities)
[‘北京‘, [‘深圳‘, ‘广州‘], ‘杭州‘]
3.5、index()
cities = ["北京","上海",["深圳","广州"],"杭州"]
print(cities.index("杭州"))
3.6、count()
cities = ["北京","上海",["深圳","广州"],"杭州"]
cities.append("北京")
cities.append("北京")
print(cities)
3.7、reverse()
cities = ["北京","上海",["深圳","广州"],"杭州"]
cities.reverse()
print(cities)
[‘杭州‘, [‘深圳‘, ‘广州‘], ‘上海‘, ‘北京‘]
3.8、sort()
# 降序
list_r.sort(reverse=True)
print(list_r)
# 升序
list_r.sort(reverse=False)
print(list_r)[‘x‘, ‘a‘, ‘C‘, ‘B‘, ‘A‘]
[‘A‘, ‘B‘, ‘C‘, ‘a‘, ‘x‘]
3.9、extend()
cities = ["北京","上海",["深圳","广州"],"杭州"]
new_cities = ["武汉","成都","重庆","南京"]
cities.extend(new_cities)
print(cities)
[‘北京‘, ‘北京‘, ‘北京‘, ‘杭州‘, ‘武汉‘, ‘成都‘, ‘重庆‘, ‘南京‘, ‘武汉‘, ‘成都‘, ‘重庆‘, ‘南京‘]
3.10、len()
cities = ["北京","上海",["深圳","广州"],"杭州"]
print(cities)
nums = len(cities)
print(nums)
[‘北京‘, ‘上海‘, [‘深圳‘, ‘广州‘], ‘杭州‘]
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