学习python列表、字典、集合的总结

#!/usr/bin/env python#_*_coding:utf-8_*_names = ['Alex',"Tenglan",'Eric']#print names[0] //python2.7不必加括号print (names[0])

#!/usr/bin/env python#_*_coding:utf-8_*_#切片:取多个元素　names = ["Alex","Tenglan","Eric","Rain","Tom","Amy"]print (names[1:4])#追加names.append("xiao")print (names)#插入names.insert(2,"强行从Eric前面插入")print (names)#修改names[2]="该换人了"print (names)

#删除del names[2]print (names)#删除指定元素names.remove("Eric")print (names)#删除列表最后一个值names.pop()print (names)

#扩展b = [1,2,3]names.extend(b)print (names)#拷贝name_copy=names.copy()print (name_copy)#统计names=['Alex', 'Tenglan', 'Amy', 'Tom', 'Amy', 1, 2, 3]print (names.count("Amy"))#排序names[-3] = '1'names[-2] = '2'names[-1] = '3'names.sort()print(names)

#反转names.reverse()print(names)#获取下标print (names.index("Amy"))

#!/usr/bin/env python#_*_coding:utf-8_*_names = ("alex","jack","eric")print (names.count("alex"))print (names.index("jack"))

#检测字符串是否由字母和数字组成print ('9aA'.isalnum())#是否整数print ('9'.isdigit())#检测字符串是否只由数字组成。这种方法是只针对unicode对象str = u"this2009"print (str.isnumeric())str = u"23443434"print (str.isnumeric())#判断字符串所包含的字符是否全部可打印。字符串包含不可打印字符，如转义字符，将返回Falseprint (str.isprintable())#字符串是否仅包含空格或制表符。注意：空格字符与空白是不同的print (str.isspace())

#判断字符串每个单词的首字母是否大写print (str.istitle())

#判断所有字母字符是否全部大写print (str.isupper())#'alex|jack|rain'print ("|".join(['alex','jack','rain']))#maketransintab = "aeiou"outtab = "12345"trantab = str.maketrans(intab, outtab)str = "this is string example....wow!!!"print (str.translate(trantab))#out: th3s 3s str3ng 2x1mpl2....w4w!!!print (msg.partition('is'))#out: ('my name ', 'is', ' {name}, and age is {age}')#替换print ("alex li, chinese name is lijie".replace("li", "LI", 1))

#大小写互换str = "this is string example....wow!!!"print (str.swapcase())print (msg.zfill(40))# out: 00000my name is {name}, and age is {age}print (msg.ljust(40,"-"))#my name is {name}, and age is {age}-----print (msg.rjust(40, "-"))#-----my name is {name}, and age is {age}# 检测一段字符串可否被当作标志符，即是否符合变量命名规则b="ddefdsdff_哈哈"print (b.isidentifier())

#!/usr/bin/env python# -*- coding: utf-8 -*-# @Time    : 2017/3/26 13:26# @Author  : corasql# @Site    : # @File    : dic.py# @Software: PyCharm Community Editioninfo = {    'stu1101': "TengLan Wu",    'stu1102': "LongZe Luola",    'stu1103': "XiaoZe Maliya",}#增加info["stu1104"] = "Python "print (info)

#修改info['stu1101'] ="test"print (info)#删除info.pop("stu1101") #标准删除姿势print (info)del info['stu1103']  # 换个姿势删除print (info)#随机删除info = {'stu1102': 'LongZe Luola', 'stu1103': 'XiaoZe Maliya'}info.popitem()print (info)#查找info = {'stu1102': 'LongZe Luola', 'stu1103': 'XiaoZe Maliya'}print ("stu1102" in info) #标准用法print (info.get("stu1102"))  #获取print (info["stu1102"]) #同上，但是看下面

print (info["stu1105"])  #如果一个key不存在，就报错，get不会，不存在只返回None#循环dict#方法1for key in info:    print(key,info[key])#方法2for k,v in info.items(): #会先把dict转成list,数据里大时莫用    print(k,v)

s = set([3,5,9,10])      #创建一个数值集合  t = set("Hello")         #创建一个唯一字符的集合  a = t | s          # t 和 s的并集  b = t & s          # t 和 s的交集  c = t – s          # 求差集（项在t中，但不在s中）  d = t ^ s          # 对称差集（项在t或s中，但不会同时出现在二者中）

t.add('x')  # 添加一项  s.update([10,37,42])  # 在s中添加多项  使用remove()可以删除一项：  t.remove('H')

len(s)  set 的长度  x in s  测试 x 是否是 s 的成员  x not in s  测试 x 是否不是 s 的成员  s.issubset(t)  s = t  测试是否 t 中的每一个元素都在 s 中  s.union(t)  s | t  返回一个新的 set 包含 s 和 t 中的每一个元素  s.intersection(t)  s & t

返回一个新的 set 包含 s 和 t 中的公共元素  s.difference(t)  s - t  返回一个新的 set 包含 s 中有但是 t 中没有的元素  s.symmetric_difference(t)  s ^ t  返回一个新的 set 包含 s 和 t 中不重复的元素  s.copy()  返回 set “s”的一个浅复制

#!/usr/bin/env python# -*- coding: utf-8 -*-# @Time    : 2017/3/26 14:00# @Author  : corasql# @Site    : # @File    : file.py# @Software: PyCharm Community Editionf = open('lyrics')  # 打开文件first_line = f.readline()print('first line:', first_line)  # 读一行print('我是分隔线'.center(50, '-'))data = f.read()  # 读取剩下的所有内容,文件大时不要用print(data)  # 打印文件f.close()  # 关闭文件

python2#!/usr/bin/env python# -*- coding: utf-8 -*-# @Time    : 2017/3/26 13:55# @Author  : corasql# @Site    : # @File    : decode2.py# @Software: PyCharm Community Editionimport sysprint(sys.getdefaultencoding())

msg = "我爱北京天安门"msg_gb2312 = msg.decode("utf-8").encode("gb2312")gb2312_to_gbk = msg_gb2312.decode("gbk").encode("gbk")print(msg)print(msg_gb2312)print(gb2312_to_gbk)python3#!/usr/bin/env python# -*- coding: utf-8 -*-# @Time    : 2017/3/26 13:51# @Author  : corasql# @Site    : # @File    : decode.py# @Software: PyCharm Community Editionimport sysprint(sys.getdefaultencoding())

msg = "我爱北京天安门"#msg_gb2312 = msg.decode("utf-8").encode("gb2312")msg_gb2312 = msg.encode("gb2312") #默认就是unicode,不用再decode,喜大普奔gb2312_to_unicode = msg_gb2312.decode("gb2312")gb2312_to_utf8 = msg_gb2312.decode("gb2312").encode("utf-8")print(msg)print(msg_gb2312)print(gb2312_to_unicode)print(gb2312_to_utf8)