python基本数据类型操作
str 字符串
#1.进行字符串转换 首字母转换成大写 # name = 'wangjianhui' # v = name.capitalize() # print(v) #2. 字符转换小写 # name = 'WangJianHui' #将所有的字符串转换成小写 包括多种语言 # v = name.casefold() # print(v) # name = 'WangJianHui' #将所有字符转换成小写,只限于英文 # v = name.lower() # print(v) #3 填充空白 # name = 'wangjianhui' #填充空白 将字符串内容居中 # v = name.center(50,'*') # print(v) #4 查询索引 # name = 'wangjianhui123321' 查询出现字符的次数 # v = name.count('1') # v = name.count('wang',0,15)指定查询位置以某索引开始到某索引结束 # print(v) #5查询是否已某字段开始或结束 # name = 'wangjianhui' # v = name.endswith('hui') # print(v) # v = name.startswith('wang') #6 找到制表符\t,进行替换(包含前面的值) # name = 'name:\twangjianhui\nage:\t19' # v = name.expandtabs(10)# # print(v) #7 查询索引位置 # name = 'wangjianhui' # v = name.index('w') 字符串中不存在的内容 查找会报错 # print(v) # v = name.find('w') 字符串不存在的内容 查找返回-1 # print(v) #8 字符串格式化方法 # infomesion = 'name:%sage:%sjob:%s' %s占位符 # print(infomesion%('wangjianhui',19,'it')) # infomesion = 'name:{0};age:{1};job{2}' format方法 # v = infomesion.format('wangjianhui',19,'it') # print(v) # infomesion = 'name:{name};age:{age};job{nianling}' # v = infomesion.format(name='wangjianhui',age=19,nianling='it') # print(v) # infomesion = 'name:{name};age:{age};job{nianling}' format_map 以字典的形式进行填充 # v = infomesion.format_map({'name':'wangjianhui','age':19,'nianling':'it'}) # print(v) #9字符串内容进行判断 #是否是数字、汉字不能包含特殊符号 # name = 'wangjianhui男子汉1' # v = name.isalnum() # print(v) #判断是否是数字 # name = '②' # v1 = name.isdecimal() #只能判断是否为阿拉伯数字 # v2 = name.isdigit() #特殊数字如②也可识别 # v3 = name.isnumeric()#阿拉伯数字及② 二都可识别 # print(v1,v2,v3) #10 #判断是否是标识符 # name = 'wangjianhui' # v = name.isidentifier() # print(v) #11 #判断是否全部是小写 # name = 'WangJianHui' # v1 = name.islower() # v2 = name.isupper() # print(v1,v2) #12 #全部变大写 对应全部小写lower # name = 'wangjianhui' # v = name.upper() # print(v) # 13 # 是否包含隐含的xx # name = "钓鱼要钓刀鱼,\n刀鱼要到岛上钓" # v = name.isprintable() # print(v) # 14 # 是否全部是空格 # name = ' ' # v = name.isspace() # print(v) #15 #内部循环每个元素 # name = 'wangjianhui' # v = '_'.join(name) # print(v) # name = ['王建辉','金丽珍'] # v = '爱'.join(name) # print(v) #16 #字符替换 # name = 'aleX' # v = name.replace('l','p') # print(v) #17 #转换字节类型 # name = '王建辉' # v1 = name.encode(encoding='utf-8') # v2 = name.encode(encoding='gbk') # print(v1,v2) #18左右填充 # center,rjust,ljust # name = 'wangjianhui' # v = name.ljust(20,'*') # print(v) #19对应关系加翻译 # m = str.maketrans('wangjianhui','123456') # name = 'wangxiaoerweqrrwrwrq;wfasfs' # v = name.translate(m) # print(v) #20保留分割的元素 # content = "李泉SB刘康SB刘浩SB刘一" # v = content.replace('SB','Love') # print(v) # v = content.replace('SB','Love',1) 指定几个字符替换 # print(v) # 21,移除空白,\n,\t,自定义 # name = 'alex\t' # v = name.strip() # 空白,\n,\t # print(v) # 22. 大小写转换 # name = "Alex" # v = name.swapcase() # print(v) #23填充0 # name = 'wangjianhui' # v = name.zfill(30) # # name1 = 'wangjianhui1' # v = name + name1 # print(v) ###### 字符串功能总结: # name = 'alex' 创建字符串给变量 或str() # name.upper() 转换为大写 # name.lower()转换为小写 # name.split() 切割 # name.find() 查找索引 没有不会报错 # name.strip() 移除空白或指定符号 # name.startswith()以什么内容开始 # name.format() 表格填充 # name.replace() 保留分割元素替换 # "alex".join(["aa",'bb']) 添加分割 ###### 额外功能: # name = "alex" # name[0] # name[0:3] # name[0:3:2] # len(name) # for循环,每个元素是字符 # for i len(name): # print(name[i])
int 整数
#1. 获取当前数值二进制最小位数 # name = 10 # v = name.bit_length() # print(v) #2.获取当前数据的字节表示 # name = 15 # v = name.to_bytes(5,byteorder='big') #位数表示 从后往前正常显示 # v1 = name.to_bytes(5,byteorder='little')#从前往后反向显示 # print(v,v1)
bool 布尔值
#1. False True #0为False 1或其他为True # print(bool(0))
list 列表
# user_list = ['李泉','刘一','刘康','豆豆','小龙'] # 可变类型 # PS: #功能集合 #1.追加 append # user_list = ['李泉','刘一','刘康','豆豆','小龙'] # user_list.append('王二') # print(user_list) #2.清空 clear # user_list = ['李泉','刘一','刘康','豆豆','小龙'] # user_list.clear() # print(user_list) #3.拷贝 浅拷贝copy # user_list = ['李泉','刘一','刘康','豆豆','小龙'] # user_list1 = user_list.copy() # print(user_list1) #4.计数 统计某个列表字符数量 count # user_list = ['李泉','刘一','刘康','豆豆','小龙'] # user_c = user_list.count('小龙') # print(user_c) #5.扩展列表 extend # user_list = ['李泉','刘一','刘康','豆豆','小龙'] # user_list.extend(['王建辉','王二小']) # print(user_list) #6.查找元素索引,没有则报错 index # user_list = ['李泉','刘一','刘康','豆豆','小龙'] # v = user_list.index('小龙') # print(v) #7.删除 pop(按照索引删除,并保存删除值) remove(指定删除内容不保存) del(索引删除不保留) # user_list = ['李泉','刘一','刘康','豆豆','小龙'] # v = user_list.pop(1) # print(v,user_list) # del user_list[1] # print(user_list) # user_list.remove('李泉') # print(user_list) #8.列表翻转 reverse # user_list = ['李泉','刘一','刘康','豆豆','小龙'] # user_list.reverse() # print(user_list) #9.排序 sort #user_list = [1,'李泉','刘一','刘康','豆豆','小龙']#数字和字符不能进行排序 # user_list = [10,20,5,67,44] # user_list.sort() #从小到大 # print(user_list) # user_list.sort(reverse=True/False) 从大到小或从小到大 # print(user_list) #10. ###### 额外: # user_list = ['李泉','刘一','李泉','刘康','豆豆','小龙'] # user_list[0] # user_list[1:5:2] #显示从索引开始结束 跳着显示 # del user_list[3] # for i in user_list: #循环显示 # print(i) # user_list[1] = '姜日天' 覆盖或修改 # user_list = ['李泉','刘一','李泉','刘康','豆豆',['日天','日地','泰迪'],'小龙'] #嵌套
range,enumrate
# 1. 请输出1-10 # 2.7: 立即生成所有数字 # range(1,11) # 生成 1,23,,4,56.10 # 3.x: 不会立即生成,只有循环迭代时,才一个一个生成 # for i in range(1,11): # # print(i) # for i in range(1,11,2): # # print(i) # for i in range(10,0,-1): # # print(i) # 2. range: 三个参数 # # li = ['eric','alex','tony'] # # range,len,li循环 # for i in range(0,len(li)): # ele = li[i] # print(ele) # li = ['eric','alex','tony'] # for i in li: # print(i) # for i in range(0,len(li)): # print(i+1,li[i]) # enumerate额外生成一列有序的数字 # li = ['eric','alex','tony'] # for i,ele in enumerate(li,1): # print(i,ele) # # v = input('请输入商品序号:') # v = int(v) # item = li[v-1] # print(item)
tuple:元组,不可被修改的列表;不可变类型
#创建元组 #name = ('wnagjianhui','wangxiaoer','wangerxiao') #1.获取元祖字符个数 # name = ('wangjianhui','wangxiaoer','wangerxiao') # v = name.count('wangjianhui') # print(v) #2.获取索引位置 # name = ('wangjianhui','wangxiaoer','wangerxiao') # v = name.index('wangjianhui') # print(v) #3.额外 # user_tuple = ('alex','eric','seven','alex') # for i in user_tuple: # print(i) # v = user_tuple[0] # v = user_tuple[0:2] # print(v) # user_tuple = ('alex','eric','seven',['陈涛','刘浩','赵芬芬'],'alex') # user_tuple[0] = 123 x # user_tuple[3] = [11,22,33] x # user_tuple[3][1] = '刘一' # print(user_tuple) # li = ['陈涛','刘浩',('alex','eric','seven'),'赵芬芬'] # ****** 元组最后,加逗号 ****** # li = ('alex',) # print(li)
dict:字典: 可变类型
#1.清空字典 clear # namedic = {'name':'wangjianhui','age':19,'job':'it'} # namedic.clear() # print(namedic) #2.浅拷贝 copy # namedic = {'name':'wangjianhui','age':19,'job':'it'} # namedic1 = namedic.copy() # print(namedic1) #3.根据key值获取value值,不存在不报错 get # namedic = {'name':'wangjianhui','age':19,'job':'it'} get查找根据key找value 找不到不报错 # namedic1 = namedic.get('name') # print(namedic1) #4.删除key对应的value值 并保存删除值 # namedic = {'name':'wangjianhui','age':19,'job':'it'} # namedic1 = namedic.pop('name') # print(namedic1,namedic) # 5. 随机删除键值对,并获取到删除的键值 popitem # dic = {'k1':'v1','k2':'v2'} # v = dic.popitem() # print(dic) # print(v) # v = dic.popitem() # ('k2', 'v2') # print(dic) # print(v[0],v[1]) #6.增加字典 如果存在则不作操作 # namedic = {'name':'wangjianhui','age':19,'job':'it'} # namedic.setdefault('wait','1111') # print(namedic) #7.批量增加或修改 # namedic = {'name':'wangjianhui','age':19,'job':'it'} # namedic.update({'name':'wangxiaoer','wait':'111'}) # print(namedic) #8.批量创建字典 # dic = dict.fromkeys(['k1','k2','k3'],321) # print(dic) # ########## 额外: # - 字典可以嵌套 # - 字典key: 必须是不可变类型 # dic = { # 'k1': 'v1', # 'k2': [1,2,3,], # (1,2): 'lllll', # 1: 'fffffffff', # 111: 'asdf', # } # print(dic) # key: # - 不可变 # - True,1 # dic = {'k1':'v1'} # del dic['k1']
set集合
# s1 = {"alex",'eric','tony','李泉','李泉11'} # s2 = {"alex",'eric','tony','刘一'} # 1.s1中存在,s2中不存在 # v = s1.difference(s2) # print(v) # #### s1中存在,s2中不存在,然后对s1清空,然后在重新复制 # s1.difference_update(s2) # print(s1) # 2.s2中存在,s1中不存在 # v = s2.difference(s1) # print(v) # 3.s2中存在,s1中不存在 # s1中存在,s2中不存在 # v = s1.symmetric_difference(s2) # print(v) # 4. 交集 # v = s1.intersection(s2) # print(v) # 5. 并集 # v = s1.union(s2) # print(v) # 6. 移除 # s1 = {"alex",'eric','tony','李泉','李泉11'} # s1.discard('alex') # print(s1) # s1 = {"alex",'eric','tony','李泉','李泉11'} # s1.update({'alex','123123','fff'}) # print(s1) # ##### 额外: # s1 = {"alex",'eric','tony','李泉','李泉11'} # for i in s1: # print(i) # s1 = {"alex",'eric','tony','李泉','李泉11',(11,22,33)} # for i in s1: # print(i)