python-列表方法（list）知识整理

2020-01-21 14:37:23 浏览数 (1)
代码语言：javascript复制
!/usr/bin/env python
# -*- coding:utf-8 -*-
# __author__:anxu.qi
# Date:2018/11/29

列表list
:一个队列，一个排列整齐的队伍
：列表内的个体称作元素，由若干元素组成列表
：元素可以是任意对象（数字、字符串、对象、列表等）
：列表内元素有顺序，可以使用索引
：线性的数据结构
：使用[]表示
代码语言：javascript复制
# 字符串操作
# names = ["NingTao", "RenBaiqing", "GuoYue", "RenBaiqing"]

# ################### 列表的查 ###############################
# # 索引
# print(names[3]) # 查询出下标为3的值
# # RenBaiqing
# print(names[0], names[2])   # 查询出下标为0,2的值
# # NingTao GuoYue
#
# # 切片  顾头不顾尾
# print(names[1:3])   # 查询下标为1到3的值，但不包括3的值
# # ['RenBaiqing', 'GuoYue']
# print(names[-1])    # 查询最后一个值
# # RenBaiqing
# print(names[-3:-1])  # 查询数两个值
# # ['RenBaiqing', 'GuoYue']
# print(names[-3:])  # 查询倒数3个值
# # ['RenBaiqing', 'GuoYue', 'RenBaiqing']
# print(names[0:3])  # 查询下标为0-3的值，不包括下标3的值
# # ['NingTao', 'RenBaiqing', 'GuoYue']
# print(names[:3])  # 注：如果前面的是0的话可以省略掉
# # ['NingTao', 'RenBaiqing', 'GuoYue']
# print(names.index("RenBaiqing"))  # 查询 RenBaiqing的下标值
# # 1
# print(names[names.index("RenBaiqing")])
# # RenBaiqing

# ################### 列表的增 ###############################
# names = ["NingTao", "RenBaiqing", "GuoYue", "RenBaiqing"]
# names.append("FuZhiqiang")   # 追加到列表最后
# # ['NingTao', 'RenBaiqing', 'GuoYue', 'RenBaiqing', 'FuZhiqiang']
# print(names)
# # ['NingTao', 'RenBaiqing', 'GuoYue', 'RenBaiqing']
# 注 新增的话只能一次增加一个
# names.insert(1, "FuZhiqiang")  # 插入到下标为1的位置，原来的将被往后推。
# print(names)
# # ['NingTao', 'FuZhiqiang', 'RenBaiqing', 'GuoYue', 'RenBaiqing']

# ################### 列表的删除 ###############################
# 第一种：names.remove("RenBaiqing")  # 直接填写值
# names.remove("RenBaiqing")  # 删除列表中的 RenBaiqing

# 第二种 del names[4]   # 填写的是下标
# del names[4] # 填写的是值的下标   # 删除下标为4的值

# 第三种 name.pop
# names.pop()  # 默认不填写下标是删除最后一个
# names.pop(2)  # 指定下标后，删除下标的位置

# 第四中 del names
# 删除列表变量名，直接删除整个变量

# ################### 列表的改 ###############################
# print(names)
# # ['NingTao', 'FuZhiqiang', 'RenBaiqing', 'GuoYue', 'RenBaiqing']
# names[1] = "YanWen"   # 将 FuZhiqing 替换为 YangWen
# # ['NingTao', 'YanWen', 'RenBaiqing', 'GuoYue', 'RenBaiqing']
# names2 = ["NingTao", "RenBaiqing", "GuoYue", "RenBaiqing"]
# print(names2.index("RenBaiqing"))

# ################### 列表统计(count) ###############################
# print(names.count("NingTao"))
# # 2

# ################### 列表清空(clear) ###############################
# names.clear()  # 清空整个列表
# print(names)
# # []

# ################### 列表反转(reverse) ###############################
# names = ["NingTao", "RenBaiqing", "GuoYue", "RenBaiqing"]
# names.reverse()
# print(names)
# # ['RenBaiqing', 'GuoYue', 'RenBaiqing', 'NingTao']

# ################### 列表排序(sort) ###############################
# 排序规则： 特殊符号 --》 数字 --》 大写 --》 小写
# 是按照ASCII码中的排序来的
# names = ["3NingTao", "rRenBaiqing", "#GuoYue", "RenBaiqing"]
# names.sort()
# print(names)
# # ['#GuoYue', '3NingTao', 'RenBaiqing', 'rRenBaiqing']

# ################### 列表扩展 （extend）###############################
# names = ["3NingTao", "rRenBaiqing", "#GuoYue", "RenBaiqing"]
# names2 = [1,2,3,4,5,6]
# names.extend(names2)
# del names2
# # print(names,names2)
# print(names)
# # ['3NingTao', 'rRenBaiqing', '#GuoYue', 'RenBaiqing', 1, 2, 3, 4, 5, 6] [1, 2, 3, 4, 5, 6]

# ################### 列表复制 (浅 copy) ###############################
# 浅copy，只copy一次，是因为第一次的内存地址是又克隆的一份，而其他的地址没有复制，还是用的原来的内存地址，所有会变
# names = ["3NingTao", "rRenBaiqing",["aliyun","jack"], "#GuoYue", "RenBaiqing","XiaoMing"]
# names2 = names.copy()
# print(names)
# # ['3NingTao', 'rRenBaiqing', ['aliyun', 'jack'], '#GuoYue', 'RenBaiqing', 'XiaoMing']
# print(names2)
# # ['3NingTao', 'rRenBaiqing', ['aliyun', 'jack'], '#GuoYue', 'RenBaiqing', 'XiaoMing']
# names[4] = "小明"
# names2[2][0] = "ALIYUN"
# print(names)
# # ['3NingTao', 'rRenBaiqing', ['ALIYUN', 'jack'], '#GuoYue', '小明', 'XiaoMing']
# print(names2)
# # ['3NingTao', 'rRenBaiqing', ['ALIYUN', 'jack'], '#GuoYue', 'RenBaiqing', 'XiaoMing']

举例：银行同一账号，多个存款人
代码语言：javascript复制
# ################### 列表复制 (深 copy.deecopy) ###############################
import copy
# 深copy 是完全独立的复制列表 ，如果是数据量特别大的情况下，这样做是不合适的，因为将又开辟一份内存空间。
names = ['3NingTao', 'rRenBaiqing', ['aliyun', 'jack'], '#GuoYue', 'RenBaiqing', 'XiaoMing']
names2 = copy.deepcopy(names)
print(names)
# ['3NingTao', 'rRenBaiqing', ['aliyun', 'jack'], '#GuoYue', 'RenBaiqing', 'XiaoMing']
print(names2)
# ['3NingTao', 'rRenBaiqing', ['aliyun', 'jack'], '#GuoYue', 'RenBaiqing', 'XiaoMing']
names[2][0] = "ALIYUN"
print(names)
# ['3NingTao', 'rRenBaiqing', ['ALIYUN', 'jack'], '#GuoYue', 'RenBaiqing', 'XiaoMing']
print(names2)
# ['3NingTao', 'rRenBaiqing', ['aliyun', 'jack'], '#GuoYue', 'RenBaiqing', 'XiaoMing']
代码语言：javascript复制
names = ['3NingTao', 'rRenBaiqing', ['aliyun', 'jack'], '#GuoYue', 'RenBaiqing', 'XiaoMing',"hehe"]
print(names[0::2])
print(names[::2])
print(names[:-1:2])
代码语言：javascript复制
# ################### 列表 ###############################
代码语言：javascript复制
# #!/usr/bin/env python
# # -*- coding:utf-8 -*-
# # __author__:anxu.qi
# # Date:2018/11/19
# ######################### 列表 #################################
aa_list = ["tami","beijing","fengshan","fengtai","apache","nginx"]
# print(aa_list)
## 索引
print(aa_list[0])
# tami
## 切片
print(aa_list[0:2])
# ['tami', 'beijing']
##  len
print(aa_list[2:len(aa_list)])
# ['fengshan', 'fengtai', 'apache', 'nginx']

################# for  ################
# aa_list = ["tami","beijing","fengshan","fengtai","apache","nginx"]
## 循环
for i in aa_list:
    print(i)
"""
tami
beijing
fengshan
fengtai
apache
nginx
# """
############################# 列表内布提供的功能 ###############################

################################ append 追加 ##################################
# def append(self, p_object):
# 追加功能，在列表的最后添加
name_list = ["apache","nginx","tomcat","redis"]
print(name_list)
# ['apache', 'nginx', 'tomcat', 'redis']

name_list.append("mysql")
print(name_list)
# ['apache', 'nginx', 'tomcat', 'redis', 'mysql']

################################ count 统计次数 ##################################
# def count(self, value):
# 统计元素出现的次数
name_list = ["apache","nginx","tomcat","redis","tomcat","tomcat"]
print(name_list.count("tomcat"))
# 3

################################# extend 扩展 ##################################
# def extend(self, iterable):
# 扩展列表  iterable （可迭代的） # 相当于批量添加
name_list = ["apache","nginx","tomcat","redis"]
num_list = [11,22,33,44]
name_list.extend(num_list)
print(name_list)
# ['apache', 'nginx', 'tomcat', 'redis', 11, 22, 33, 44]

################################# index 获取索引 ##################################
# def index(self, value, start=None, stop=None):
# 获取某个元素的索引
name_list = ["apache","nginx","tomcat","redis","hehe","nginx","redis","nginx"]
print(name_list.index("redis",4,7))  # 从下边1开始，到下标6结束，不包括下标6
# 6

################################ insert 插入 ##################################
# def insert(self, index, p_object):
# 表示往索引的具体位置插入数据
name_list = ["apache","nginx","tomcat","redis"]
name_list.insert(1,"mysql")  # 先输入下标值，然后输入你要插入值。
print(name_list)
# ['apache', 'mysql', 'nginx', 'tomcat', 'redis']

################################ pop 移除 ##################################
# def pop(self, index=None):
# 默认是移除最后一个
name_list = ["apache","nginx","tomcat","redis"]
print(name_list.pop())
# redis

# 在原来列表中移除到最后一个元素，并赋值给aa
name_list = ["apache","nginx","tomcat","redis"]
aa = name_list.pop(2)
print(aa)
# redis
print(name_list)
# ['apache', 'nginx', 'tomcat']

# 可以使用下标值
name_list = ["apache","nginx","tomcat","redis"]
print(name_list.pop(2),11111111111) # pop中可以跟下标，移除的就是下标的值。
# tomcat 11111111111

################################ remove 移除 ##################################
# def remove(self, value):
# 移除某个元素 默认只移除第一个从左边匹配到的元素。
name_list = ["apache","nginx","tomcat","redis","apache","tomcat","apache"]
name2 = name_list.remove("apache")   # 默认移除从左边移除的第一个apache
print(name_list)
# [ nginx', 'tomcat', 'redis', 'apache', 'tomcat', 'apache']


################################ reverse 反转  ##################################
# def reverse(self):
# 前后顺序倒过来
name_list = ["apache","nginx","tomcat","redis"]
print(name_list.reverse())
print(name_list)
# ['redis', 'tomcat', 'nginx', 'apache']


################################ sort 排序 ##################################
# def sort(self, cmp=None, key=None, reverse=False):
# 排序
name_list = ["apache","nginx","tomcat","redis","mysql"]
# 先不进行讲解，后期再调整更新
代码语言：javascript复制
################################ del 删除指定位置的元素 ##################################
name_list = ["apache","nginx","tomcat","redis","mysql"]
del name_list[1]   # 删除列表中下标为1的元素
print(name_list)
# ['apache', 'tomcat', 'redis', 'mysql']

name_list = ["apache","nginx","tomcat","redis","mysql"]
del name_list[1:3]   #删除列表中下标1到3的元素
print(name_list)
# ['apache', 'redis', 'mysql']
代码语言：javascript复制
#################################################################################
python list

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