Python开发【第二篇】:Python基本数据类型

运算符

一、数字运算

Python开发【第二篇】:Python基本数据类型

二、比较运算

Python开发【第二篇】:Python基本数据类型

三、赋值运算

Python开发【第二篇】:Python基本数据类型

四、逻辑运算

Python开发【第二篇】:Python基本数据类型

五、成员运算

Python开发【第二篇】:Python基本数据类型

基本数据类型

一、数字

int(整型)

在32位机器上,整数的位数为32位,取值范围为-231~231-1,即-2147483648~2147483647
  在64位系统上,整数的位数为64位,取值范围为-263~263-1,即-9223372036854775808~9223372036854775807

- int
    将字符串转换为数字
        a = "123"
        print(type(a),a)

        b = int(a)
        print(type(b),b)

        num = "0011" 
        v = int(num, base=16)
        print(v)
- bit_lenght
        # 当前数字的二进制,至少用n位表示
        r = age.bit_length()

二、字符串

字符串一旦创建,不可修改
一旦修改或者拼接,都会造成重新生成字符串

字符串常用功能

  • join
  • split
  • find
  • strip
  • upper
  • lower
  • replace
# 1 首字母大写
    # test = "aLex"
    # v = test.capitalize()
    # print(v)

# 2 所有变小写,casefold更牛逼,很多未知的对相应变小写
    # v1 = test.casefold()
    # print(v1)
    # v2 = test.lower()
    # print(v2)

# 3 设置宽度,并将内容居中
    # 20 代指总长度
    # *  空白未知填充,一个字符,可有可无
    # v = test.center(20,"中")
    # print(v)

    # test = "alex"
    # v = test.ljust(20,"*")
    # print(v)

    # test = "alex"
    # v = test.rjust(20,"*")
    # print(v)

    # test = "alex"
    # v = test.zfill(20)
    # print(v)

# 4 去字符串中寻找,寻找子序列的出现次数
    # test = "aLexalexr"
    # v = test.count(‘ex‘)
    # print(v)

    # test = "aLexalexr"
    # v = test.count(‘ex‘,5,6)
    # print(v)

# 5
    # 以什么什么结尾
    # 以什么什么开始
    # test = "alex"
    # v = test.endswith(‘ex‘)
    # v = test.startswith(‘ex‘)
    # print(v)

# 6 expandtabs,断句20,
    # test = 
    # v = test.expandtabs(20)
    # print(v)

# 7 从开始往后找,找到第一个之后,获取其未知
    # > 或 >=
    # test = "alexalex"
    # 未找到 -1
    # v = test.find(‘ex‘)
    # print(v)

# 8 index找不到,报错   忽略
    # test = "alexalex"
    # v = test.index(‘8‘)
    # print(v)

# 9 格式化,将一个字符串中的占位符替换为指定的值
    # test = ‘i am {name}, age {a}‘
    # print(test)
    # v = test.format(name=‘alex‘,a=19)
    # print(v)

    # test = ‘i am {0}, age {1}‘
    # print(test)
    # v = test.format(‘alex‘,19)
    # print(v)

# 10 格式化,传入的值 {"name": ‘alex‘, "a": 19}
    # test = ‘i am {name}, age {a}‘
    # v1 = test.format(name=‘df‘,a=10)
    # v2 = test.format_map({"name": ‘alex‘, "a": 19})

# 11 字符串中是否只包含 字母和数字
    # test = "123"
    # v = test.isalnum()
    # print(v)
    # str

# 12 是否是字母,汉子
    # test = "as2df"
    # v = test.isalpha()
    # print(v)

# 13 当前输入是否是数字
    # test = "二" # 1,②
    # v1 = test.isdecimal()
    # v2 = test.isdigit()
    # v3 = test.isnumeric()
    # print(v1,v2,v3)

# 14 是否存在不可显示的字符
    # \t   制表符
    # \n   换行
    # test = "oiuas\tdfkj"
    # v = test.isprintable()
    # print(v)

# 15 判断是否全部是空格
    # test = ""
    # v = test.isspace()
    # print(v)

# 16 判断是否是标题
    # test = "Return True if all cased characters in S are uppercase and there is"
    # v1 = test.istitle()
    # print(v1)
    # v2 = test.title()
    # print(v2)
    # v3 = v2.istitle()
    # print(v3)

# 17 ***** 将字符串中的每一个元素按照指定分隔符进行拼接
    # test = "你是风儿我是沙"
    # print(test)
    # # t = ‘ ‘
    # v = "_".join(test)
    # print(v)

# 18 判断是否全部是大小写 和 转换为大小写
    # test = "Alex"
    # v1 = test.islower()
    # v2 = test.lower()
    # print(v1, v2)

    # v1 = test.isupper()
    # v2 = test.upper()
    # print(v1,v2)
# 19
    # 移除指定字符串
    # 有限最多匹配
    # test = "xa"
    # # v = test.lstrip(‘xa‘)
    # v = test.rstrip(‘9lexxexa‘)
    # # v = test.strip(‘xa‘)
    # print(v)

    # test.lstrip()
    # test.rstrip()
    # test.strip()
    # 去除左右空白
    # v = test.lstrip()
    # v = test.rstrip()
    # v = test.strip()
    # print(v)
    # print(test)
    # 去除\t \n
    # v = test.lstrip()
    # v = test.rstrip()
    # v = test.strip()
    # print(v)

# 20 对应关系替换
    # test =  "aeiou"
    # test1 = "12345"

    # v = "asidufkasd;fiuadkf;adfkjalsdjf"
    # m = str.maketrans("aeiou", "12345")
    # new_v = v.translate(m)
    # print(new_v)

# 21 分割为三部分
    # test = "testasdsddfg"
    # v = test.partition(‘s‘)
    # print(v)
    # v = test.rpartition(‘s‘)
    # print(v)

# 22 分割为指定个数
    # v = test.split(‘s‘,2)
    # print(v)
    # test.rsplit()

# 23 分割,只能根据,true,false:是否保留换行
    # test = "asdfadfasdf\nasdfasdf\nadfasdf"
    # v = test.splitlines(False)
    # print(v)

#  24 以xxx开头,以xx结尾
    # test = "backend 1.1.1.1"
    # v = test.startswith(‘a‘)
    # print(v)
    # test.endswith(‘a)

# 25 大小写转换
    # test = "aLex"
    # v = test.swapcase()
    # print(v)

# 26 字母,数字,下划线 : 标识符 def  class
    # a = "def"
    # v = a.isidentifier()
    # print(v)

# 27 将指定字符串替换为指定字符串
    # test = "alexalexalex"
    # v = test.replace("ex",‘bbb‘)
    # print(v)
    # v = test.replace("ex",‘bbb‘,2)
    # print(v)
# 一、for循环
    # for 变量名 in 字符串:
    #     变量名
    # break
    # continue

    # index = 0
    # while index < len(test):
    #     v = test[index]
    #     print(v)
    #
    #     index += 1
    # print(‘=======‘)

    # for zjw in test:
    #     print(zjw)

    # test = "郑建文妹子有种冲我来"
    # for item in test:
    #     print(item)
    #     break

    # for item in test:
    #     continue
    #     print(item)

# 二、索引,下标,获取字符串中的某一个字符
    # v = test[3]
    # print(v)

# 三、切片
    # v = test[0:-1] # 0=<  <1
    # print(v)

# 四、获取长度
    # Python3: len获取当前字符串中由几个字符组成
    # v = len(test)
    # print(v)

# 五、获取连续或不连续的数字,
    # Python2中直接创建在内容中
    # python3中只有for循环时,才一个一个创建
    # r1 = range(10)
    # r2 = range(1,10)
    # r3 = range(1,10,2)
    # 帮助创建连续的数字,通过设置步长来指定不连续
    # v = range(0, 100, 5)
    #
    # for item in v:
    #     print(item)

三、列表

列表格式

  • 列表中可以嵌套任何类型
  • 中括号括起来
  • ,分割每个元素
  • 列表中的元素可以是 数字,字符串,列表,布尔值..所有的都能放进去
  • “集合”,内部放置任何东西
  • 列表,有序;元素可以被修改
#########################list类中提供的方法 #######################

# li = [11, 22, 33, 22, 44]
# 参数
# 1. 原来值最后追加
# 对象.方法(..)   # li对象调用append方法
# li.append(5)
# li.append("alex")
# li.append([1234,2323])
# print(li)

# 2 清空列表
# li.clear()
# print(li)

# 3 拷贝,浅拷贝
# v = li.copy()
# print(v)
# 4. 计算元素出现的次数
# v = li.count(22)
# print(v)

# 5. 扩展原列表,参数:可迭代对象
# li = [11, 22, 33, 22, 44]
# li.append([9898,"不得了"])
# [11, 22, 33, 22, 44, [9898, ‘不得了‘]]

# li.extend([9898,"不得了"])
# for i in [9898,"不得了"]:
#     li.append(i)
# [11, 22, 33, 22, 44, 9898, ‘不得了‘]
#
# li.extend("不得了")
# print(li)

# 6. 根据值获取当前值索引位置(左边优先)
# li = [11, 22, 33, 22, 44]
# v= li.index(22)
# print(v)

# 7. 在指定索引位置插入元素
# li = [11, 22, 33, 22, 44]
# li.insert(0,99)
# print(li)

# 8、 删除某个值(1.指定索引;2. 默认最后一个),并获取删除的值
# li = [11, 22, 33, 22, 44]
# v = li.pop()
# print(li)
# print(v)

# li = [11, 22, 33, 22, 44]
# v = li.pop(1)
# print(li)
# print(v)
# 9. 删除列表中的指定值,左边优先
# li = [11, 22, 33, 22, 44]
# li.remove(22)
# print(li)
# PS: pop remove del li[0]    del li[7:9]   clear

# 10 将当前列表进行翻转
# li = [11, 22, 33, 22, 44]
# li.reverse()
# print(li)

# 11 列表的排序
# li = [11,44, 22, 33, 22]
# li.sort()
# li.sort(reverse=True)
# print(li)
####################################### 深灰魔法 #######################################

# 1.
# 索引取值
print(li[3])

# 2 切片,切片结果也是列表
print(li[3:-1])

# 3 for循环
# while循环
for item in li:
    print(item)
"""
# 列表元素,可以被修改

# li = [1, 12, 9, "age", ["石振文", ["19", 10], "庞麦郎"], "alex", True]

############## 4 索引
# 修改
# li[1] = 120
# print(li)
# li[1] = [11,22,33,44]
# print(li)

# 删除,第一种方式
# del li[1]
# print(li)
############## 5 切片
# 修改
# li[1:3] = [120,90]
# print(li)
# 删除
# del li[2:6]
# print(li)

# 6 in 操作
# li = [1, 12, 9, "age", ["石振文", ["19", 10], "庞麦郎"], "alex", True]
# v1 = "石振文" in li
# print(v1)
# v2 = "age" in li
# print(v2)

# 7 转换
# 字符串转换列表   li =  list("asdfasdfasdf"), 内部使用for循环
# s = "pouaskdfauspdfiajsdkfj"
# new_li = list(s)
# print(new_li)

# 列表转换成字符串,
# 需要自己写for循环一个一个处理: 既有数字又有字符串
# li = [11,22,33,"123","alex"]
# # r = str(li) # ‘[11,22,33,"123","alex"]‘
# # print(r)
# s = ""
# for i in li:
#     s = s + str(i)
# print(s)
# 直接使用字符串join方法:列表中的元素只有字符串
# li = ["123","alex"]
# v = "".join(li)
# print(v)

四、元组

元组,元素不可被修改,不能被增加或者删除

tu = (11,22,33,44)
tu.count(22),获取指定元素在元组中出现的次数

tu.index(22)获取指定元素在元组的索引
# 1. 书写格式
# tu = (111,"alex",(11,22),[(33,44)],True,33,44,)
# 一般写元组的时候,推荐在最后加入 ,
# 元素不可被修改,不能被增加或者删除
# 2. 索引
# v = tu[0]
# print(v)

# 3. 切片
# v = tu[0:2]
# print(v)

# 4. 可以被for循环,可迭代对象
# for item in tu:
#     print(item)

# 5. 转换
# s = "asdfasdf0"
# li = ["asdf","asdfasdf"]
# tu = ("asdf","asdf")
#
# v = tuple(s)
# print(v)

# v = tuple(li)
# print(v)

# v = list(tu)
# print(v)

# v = "_".join(tu)
# print(v)

# li = ["asdf","asdfasdf"]
# li.extend((11,22,33,))
# print(li)

# 6.元组的一级元素不可修改/删除/增加
# tu = (111,"alex",(11,22),[(33,44)],True,33,44,)
# # 元组,有序。
# # v = tu[3][0][0]
# # print(v)
# # v=tu[3]
# # print(v)
# tu[3][0] = 567
# print(tu)

五、字典

  • 字典无序
  • 字典的value可以是任何值
  • 布尔值(1,0)、列表、字典不能作为字典的key**
# 1 根据序列,创建字典,并指定统一的值
# v = dict.fromkeys(["k1",123,"999"],123)
# print(v)

# 2 根据Key获取值,key不存在时,可以指定默认值(None)
# v = dic[‘k11111‘]
# print(v)
# v = dic.get(‘k1‘,111111)
# print(v)

# 3 删除并获取值
# dic = {
#     "k1": ‘v1‘,
#     "k2": ‘v2‘
# }
# v = dic.pop(‘k1‘,90)
# print(dic,v)
# k,v = dic.popitem()
# print(dic,k,v)

# 4 设置值,
# 已存在,不设置,获取当前key对应的值
# 不存在,设置,获取当前key对应的值
# dic = {
#     "k1": ‘v1‘,
#     "k2": ‘v2‘
# }
# v = dic.setdefault(‘k1111‘,‘123‘)
# print(dic,v)

# 5 更新
# dic = {
#     "k1": ‘v1‘,
#     "k2": ‘v2‘
# }
# dic.update({‘k1‘: ‘111111‘,‘k3‘: 123})
# print(dic)
# dic.update(k1=123,k3=345,k5="asdf")
# print(dic)
  • 字典的value可以是任何值
# info = {
#     "k1": 18,
#     "k2": True,
#     "k3": [
#         11,
#         [],
#         (),
#         22,
#         33,
#         {
#             ‘kk1‘: ‘vv1‘,
#             ‘kk2‘: ‘vv2‘,
#             ‘kk3‘: (11,22),
#         }
#     ],
#     "k4": (11,22,33,44)
# }
# print(info)
  • 索引方式找到指定元素
# info = {
#     "k1": 18,
#     2: True,
#     "k3": [
#         11,
#         [],
#         (),
#         22,
#         33,
#         {
#             ‘kk1‘: ‘vv1‘,
#             ‘kk2‘: ‘vv2‘,
#             ‘kk3‘: (11,22),
#         }
#     ],
#     "k4": (11,22,33,44)
# }
# # v = info[‘k1‘]
# # print(v)
# # v = info[2]
# # print(v)
# v = info[‘k3‘][5][‘kk3‘][0]
# print(v)
  • 字典支持 del 删除
# info = {
#     "k1": 18,
#     2: True,
#     "k3": [
#         11,
#         [],
#         (),
#         22,
#         33,
#         {
#             ‘kk1‘: ‘vv1‘,
#             ‘kk2‘: ‘vv2‘,
#             ‘kk3‘: (11,22),
#         }
#     ],
#     "k4": (11,22,33,44)
# }
# del info[‘k1‘]
#
# del info[‘k3‘][5][‘kk1‘]
# print(info)
  • for循环
# dict
# info = {
#     "k1": 18,
#     2: True,
#     "k3": [
#         11,
#         [],
#         (),
#         22,
#         33,
#         {
#             ‘kk1‘: ‘vv1‘,
#             ‘kk2‘: ‘vv2‘,
#             ‘kk3‘: (11,22),
#         }
#     ],
#     "k4": (11,22,33,44)
# }
# for item in info:
#     print(item)
#
# for item in info.keys():
#     print(item)

# for item in info.values():
#     print(item)

# for item in info.keys():
#     print(item,info[item])

# for k,v in info.items():
#     print(k,v)

练习题

1. 实现一个整数加法计算器(如: ?5+9 ?或 ?5+ ?9 ?或 ?5 ?+ ?9 )

n = input(‘请输入要计算的加法计算公式:‘)
v1 = n.strip()
v2 = v1.split(‘+‘)
v3 = int(v2[0])
v4 = int(v2[1])
print(v3+v4)

2. 计算用户输入的内容中有几个十进制小数?几个字母?如:asduiaf878123jkjsfd--‐213928 ?

n = input("请输入内容: ")
n1 = 0
n2 = 0
for i in n:
    if i.isalpha() == 1:
        n2 += 1
    if i.isdecimal() == 1:
        n1 += 1
print("数字有 ",n1)
print("字母, ",n2)

3. 制作趣味模板程序,
需求:等待用户输入名字、地点、爱好,根据用户的名字和爱好进行任意实现
如:敬爱可亲的 xxx,住在 xxx 地方,爱好是xxx

n = ‘敬爱可亲的{0},住在{1},爱好是{2}‘
name = input(‘请输入你的名字:‘)
addr = input(‘请输入你的住址:‘)
likes = input(‘请输入你的爱好:‘)
n1 = n.format(name,addr,likes)
print(n1)
  1. 制作随机验证码,不区分大小写。
    流程:
    ????--‐ ?用户执行程序
    ????--‐ ?给用户显示需要输入的验证码
    ????--‐ ?用户输入的值
    ????????用户输入的值和显示的值相同时现实正确信息;否则继续生成随机验证码继续等待用户输入

Python开发【第二篇】:Python基本数据类型

count = 0
while count < 3:
    def check_code():
        import random
        checkcode = ‘‘
        for i in range(4):
            current = random.randrange(0, 4)
            if current != i:
                temp = chr(random.randint(65, 90))
            else:
                temp = random.randint(0, 9)
            checkcode += str(temp)
        return checkcode

    code = check_code()
    print(code)

    n1 = input("请输入验证码:")

    n2 = n1.lower()
    n3 = code.lower()
    if n2 == n3:
        print("验证通过")
        break
    else:
        print("验证失败,请重新输入")
    count += 1

5. 开发敏感词语过滤程序,提示用户输入内容,如果用户输入的内容中包含特殊的字符:如 ?"打架" ?"斗殴",则将内容替换为

li = [‘打架‘,‘斗殴‘]
n = input(‘请输入你要搜索的内容:‘)
if n in li:
    print(n.replace(n,‘和谐社会‘))
else:
    print(n)

6. 制作表格 ?
????循环提示用户输入:用户名、密码、邮箱 ?(要求用户输入的长度不超过 20 个字符,如果超过则只有前 20 个字符有效)
????如果用户输入 ?q 或 Q ?表示不再继续输入,将用户输入的内容以表格形式打印

m = ‘{0}\t{1}\t{2}\n‘
s = ""
while True:
    name = input(‘请输入用户名:‘)
    if name == ‘q‘ or name == ‘Q‘:
        break
    if len(name) > 20:
        name = name[0:20]
    pwd = input(‘请输入密码:‘)
    if len(pwd) > 20:
        pwd = pwd[0:20]
    mails = input(‘请输入邮箱地址‘)
    if len(mails) > 20:
        mails = mails[0:20]
    n = m.format(name,pwd,mails)
    s = s + n
v = s.expandtabs(30)
print(v)
  1. 有如下值集合 [11,22,33,44,55,66,77,88,99,90...],将所有大于 66 的值保存至字典的第一个key中,将小于 66 的值保存至第二个key的值中。
    即: {‘k1‘: 大于66的所有值, ‘k2‘: 小于66的所有值}
li = [11,22,33,44,55,66,77,88,99,90]
n1 = []
n2 = []
n3 = {}
for i in li:
    if i > 66:
        n1.append(i)
    if i < 66:
        n2.append(i)
# print(n1,n2)

n3.setdefault(‘k1‘,n1)
n3.setdefault(‘k2‘,n2)

print(n3)

8.乘法表

for i in range(1,10):
    s = ‘‘
    for n in range(1,i+1):
        s += str(n)+‘ * ‘+str(i)+‘ = ‘+str(n*i)+‘\t‘
    print(s)

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