python学习-Python基本数据类型

 def capitalize(self):  
        """ 首字母变大写 """
def center(self, width, fillchar=None):  
        """ 内容居中,width:总长度;fillchar:空白处填充内容,默认无 """
def count(self, sub, start=None, end=None):  
         """ 子序列个数 """
def decode(self, encoding=None, errors=None):  
        """ 解码 """
def encode(self, encoding=None, errors=None):  
        """ 编码,针对unicode """
def endswith(self, suffix, start=None, end=None):  
        """ 是否以 xxx 结束 """
def expandtabs(self, tabsize=None):  
        """ 将tab转换成空格,默认一个tab转换成8个空格 """
 def find(self, sub, start=None, end=None):  
        """ 寻找子序列位置,如果没找到,返回 -1 """
def format(*args, **kwargs): # known special case of str.format
        """ 字符串格式化,动态参数,将函数式编程时细说 """
def index(self, sub, start=None, end=None):  
        """ 子序列位置,如果没找到,报错 """
        S.index(sub [,start [,end]]) -> int
def isalnum(self):  
        """ 是否是字母和数字 """
        """
        S.isalnum() -> bool
def isalpha(self):  
        """ 是否是字母 """
        """
        S.isalpha() -> bool
def isdigit(self):  
        """ 是否是数字 """
        """
        S.isdigit() -> bool
 def islower(self):  
        """ 是否小写 """
        """
        S.islower() -> bool
 def isspace(self):  
        """
        S.isspace() -> bool
def istitle(self):  
        """
        S.istitle() -> bool
def isupper(self):  
        """
        S.isupper() -> bool
        
def join(self, iterable):  
        """ 连接 """
        """
        S.join(iterable) -> string
def ljust(self, width, fillchar=None):  
        """ 内容左对齐,右侧填充 """
        """
 def lower(self):  
        """ 变小写 """
        """
def lstrip(self, chars=None):  
        """ 移除左侧空白 """
        """
def rfind(self, sub, start=None, end=None):  
        """
        S.rfind(sub [,start [,end]]) -> int
def rindex(self, sub, start=None, end=None):  
        """
        S.rindex(sub [,start [,end]]) -> int
def rjust(self, width, fillchar=None):  
        """
        S.rjust(width[, fillchar]) -> string
 def rpartition(self, sep):  
        """
        S.rpartition(sep) -> (head, sep, tail)

 def rsplit(self, sep=None, maxsplit=None):  
        """
        S.rsplit([sep [,maxsplit]]) -> list of strings
 def rstrip(self, chars=None):  
        """
        S.rstrip([chars]) -> string or unicode
def split(self, sep=None, maxsplit=None):  
        """ 分割, maxsplit最多分割几次 """
        """
        S.split([sep [,maxsplit]]) -> list of strings
 def splitlines(self, keepends=False):  
        """ 根据换行分割 """
        """
        S.splitlines(keepends=False) -> list of strings
def startswith(self, prefix, start=None, end=None):  
        """ 是否起始 """
        """
        S.startswith(prefix[, start[, end]]) -> bool
def strip(self, chars=None):  
        """ 移除两段空白 """
        """
        S.strip([chars]) -> string or unicode
def swapcase(self):  
        """ 大写变小写,小写变大写 """
        """
        S.swapcase() -> string
def title(self):  
        """
        S.title() -> string
 def upper(self):  
        """
        S.upper() -> string
            
def zfill(self, width):  
        """方法返回指定长度的字符串,原字符串右对齐,前面填充0。"""
        """
        S.zfill(width) -> string
方法大全

运算符

1、算数运算:
2、比较运算:
3、赋值运算:
4、逻辑运算:

5、成员运算:

基本数据类型

1、数字

int(整型)

  在32位机器上,整数的位数为32位,取值范围为-2**31~2**31-1,即-2147483648~2147483647

  在64位系统上,整数的位数为64位,取值范围为-2**63~2**63-1,即-9223372036854775808~9223372036854775807 
 
查看各个数据类型的衍生功能:cmd+单击
3.1、数字
# name=("赖晓云")
# if  "云1" in name:
#     print("yes")
# else:
#     print("no")

# int



# str
# isalpha() 判断字符串是否全为字母。
# name="laixi1aoyun"
# v=name.isalpha()
# print(v)

#isdecimal(self):判断字符串是否全为十进制字符。
# name="123339q"
# v=name.isdecimal()
# print(v)

# isdigit(self):判断字符串是否为阿拉伯数字。

# name="12331"
# v=name.isdigit()
# print(v)


#isidentifier(self):判断时候为一个合法标识符,变量、函数名、数组名、文件名

# name="1aww"
# v=name.isidentifier()
# print(v)


#islower(self):判断字符串时候全为小写字母。不包含大些字母

# name="1QQaww"
# v=name.islower()
# print(v)


#isnumeric(self):判断字符串时候全为数字,只有数字组成。

# name="122222fa"
# v=name.isnumeric()
# print(v)


#isprintable(self):是否只包含可打印字符:没有验证出false
# name="a5 @"
# v=name.isprintable()
# print(v)


#isspace(self):判断字符串时候含有空格:没验证出:true

# name="a来的5"
# v=name.isspace()
# print(v)

#istitle(self):检测字符串中所有单词拼音首字母是否为大写,且其他字母为小写


# name="Qsasq Qdsds "
# v=name.istitle()
# print(v)

# isupper(self):检测字符串包含的所有字母时候全为大写字母

# name="QQ1s"
# v=name.isupper()
# print(v)

#join(self, iterable):返回通过指定字符连接序列中元素后生成的新字符串

name="+"
sqe=("a","3")
v=name.join(sqe)
print(v)
int函数

3.2、布尔值

    真或假
  1 或 0
3.3、字符串
 
hello world
字符串常用功能:
  • 移除空白
  • 分割
  • 长度
  • 索引
  • 切片
str
# name=("赖晓云")
# if  "云1" in name:
#     print("yes")
# else:
#     print("no")

# int



# str
# isalpha() 判断字符串是否全为字母。
# name="laixi1aoyun"
# v=name.isalpha()
# print(v)

#isdecimal(self):判断字符串是否全为十进制字符。
# name="123339q"
# v=name.isdecimal()
# print(v)

# isdigit(self):判断字符串是否为阿拉伯数字。

# name="12331"
# v=name.isdigit()
# print(v)


#isidentifier(self):判断时候为一个合法标识符,变量、函数名、数组名、文件名

# name="1aww"
# v=name.isidentifier()
# print(v)


#islower(self):判断字符串时候全为小写字母。不包含大些字母

# name="1QQaww"
# v=name.islower()
# print(v)


#isnumeric(self):判断字符串时候全为数字,只有数字组成。

# name="122222fa"
# v=name.isnumeric()
# print(v)


#isprintable(self):是否只包含可打印字符:没有验证出false
# name="a5 @"
# v=name.isprintable()
# print(v)


#isspace(self):判断字符串时候含有空格:没验证出:true

# name="a来的5"
# v=name.isspace()
# print(v)

#istitle(self):检测字符串中所有单词拼音首字母是否为大写,且其他字母为小写


# name="Qsasq Qdsds "
# v=name.istitle()
# print(v)

# isupper(self):检测字符串包含的所有字母时候全为大写字母

# name="QQ1s"
# v=name.isupper()
# print(v)

#join(self, iterable):返回通过指定字符连接序列中元素后生成的新字符串

name="+"
sqe=("a","3")
v=name.join(sqe)
print(v)
函数

3.4、列表

创建列表

1 name_list = ['alex', 'seven', 'eric']
1 name_list = list(['alex', 'seven', 'eric'])

基本操作:

  • 索引
  • 切片
  • 追加
  • 删除
  • 长度
  • 切片
  • 循环
  • 包含
dd
list函数

5、元祖
创建元祖:
ages = (1122334455)
ages = tuple((1122334455))
基本操作:
  • 索引
  • 切片
  • 循环
  • 长度
  • 包含
lass tuple(object):
    """
    tuple() -> empty tuple
    tuple(iterable) -> tuple initialized from iterable's items
    
    If the argument is a tuple, the return value is the same object.
    """
    def count(self, value): # real signature unknown; restored from __doc__
        """ T.count(value) -> integer -- return number of occurrences of value """
        return 0

    def index(self, value, start=None, stop=None): # real signature unknown; restored from __doc__
        """
        T.index(value, [start, [stop]]) -> integer -- return first index of value.
        Raises ValueError if the value is not present.
        """
        return 0

    def __add__(self, y): # real signature unknown; restored from __doc__
        """ x.__add__(y) <==> x+y """
        pass

    def __contains__(self, y): # real signature unknown; restored from __doc__
        """ x.__contains__(y) <==> y in x """
        pass

    def __eq__(self, y): # real signature unknown; restored from __doc__
        """ x.__eq__(y) <==> x==y """
        pass

    def __getattribute__(self, name): # real signature unknown; restored from __doc__
        """ x.__getattribute__('name') <==> x.name """
        pass

    def __getitem__(self, y): # real signature unknown; restored from __doc__
        """ x.__getitem__(y) <==> x[y] """
        pass

    def __getnewargs__(self, *args, **kwargs): # real signature unknown
        pass

    def __getslice__(self, i, j): # real signature unknown; restored from __doc__
        """
        x.__getslice__(i, j) <==> x[i:j]
                   
                   Use of negative indices is not supported.
        """
        pass

    def __ge__(self, y): # real signature unknown; restored from __doc__
        """ x.__ge__(y) <==> x>=y """
        pass

    def __gt__(self, y): # real signature unknown; restored from __doc__
        """ x.__gt__(y) <==> x>y """
        pass

    def __hash__(self): # real signature unknown; restored from __doc__
        """ x.__hash__() <==> hash(x) """
        pass

    def __init__(self, seq=()): # known special case of tuple.__init__
        """
        tuple() -> empty tuple
        tuple(iterable) -> tuple initialized from iterable's items
        
        If the argument is a tuple, the return value is the same object.
        # (copied from class doc)
        """
        pass

    def __iter__(self): # real signature unknown; restored from __doc__
        """ x.__iter__() <==> iter(x) """
        pass

    def __len__(self): # real signature unknown; restored from __doc__
        """ x.__len__() <==> len(x) """
        pass

    def __le__(self, y): # real signature unknown; restored from __doc__
        """ x.__le__(y) <==> x<=y """
        pass

    def __lt__(self, y): # real signature unknown; restored from __doc__
        """ x.__lt__(y) <==> x<y """
        pass

    def __mul__(self, n): # real signature unknown; restored from __doc__
        """ x.__mul__(n) <==> x*n """
        pass

    @staticmethod # known case of __new__
    def __new__(S, *more): # real signature unknown; restored from __doc__
        """ T.__new__(S, ...) -> a new object with type S, a subtype of T """
        pass

    def __ne__(self, y): # real signature unknown; restored from __doc__
        """ x.__ne__(y) <==> x!=y """
        pass

    def __repr__(self): # real signature unknown; restored from __doc__
        """ x.__repr__() <==> repr(x) """
        pass

    def __rmul__(self, n): # real signature unknown; restored from __doc__
        """ x.__rmul__(n) <==> n*x """
        pass

    def __sizeof__(self): # real signature unknown; restored from __doc__
        """ T.__sizeof__() -- size of T in memory, in bytes """
        pass

tuple
View Code

6、字典(无序)
创建字典: 
1 person = {"name": "mr.wu", 'age': 18}
2 3 person = dict({"name": "mr.wu", 'age': 18}) 
class dict(object):
    """
    dict() -> new empty dictionary
    dict(mapping) -> new dictionary initialized from a mapping object's
        (key, value) pairs
    dict(iterable) -> new dictionary initialized as if via:
        d = {}
        for k, v in iterable:
            d[k] = v
    dict(**kwargs) -> new dictionary initialized with the name=value pairs
        in the keyword argument list.  For example:  dict(one=1, two=2)
    """

    def clear(self): # real signature unknown; restored from __doc__
        """ 清除内容 """
        """ D.clear() -> None.  Remove all items from D. """
        pass

    def copy(self): # real signature unknown; restored from __doc__
        """ 浅拷贝 """
        """ D.copy() -> a shallow copy of D """
        pass

    @staticmethod # known case
    def fromkeys(S, v=None): # real signature unknown; restored from __doc__
        """
        dict.fromkeys(S[,v]) -> New dict with keys from S and values equal to v.
        v defaults to None.
        """
        pass

    def get(self, k, d=None): # real signature unknown; restored from __doc__
        """ 根据key获取值,d是默认值 """
        """ D.get(k[,d]) -> D[k] if k in D, else d.  d defaults to None. """
        pass

    def has_key(self, k): # real signature unknown; restored from __doc__
        """ 是否有key """
        """ D.has_key(k) -> True if D has a key k, else False """
        return False

    def items(self): # real signature unknown; restored from __doc__
        """ 所有项的列表形式 """
        """ D.items() -> list of D's (key, value) pairs, as 2-tuples """
        return []

    def iteritems(self): # real signature unknown; restored from __doc__
        """ 项可迭代 """
        """ D.iteritems() -> an iterator over the (key, value) items of D """
        pass

    def iterkeys(self): # real signature unknown; restored from __doc__
        """ key可迭代 """
        """ D.iterkeys() -> an iterator over the keys of D """
        pass

    def itervalues(self): # real signature unknown; restored from __doc__
        """ value可迭代 """
        """ D.itervalues() -> an iterator over the values of D """
        pass

    def keys(self): # real signature unknown; restored from __doc__
        """ 所有的key列表 """
        """ D.keys() -> list of D's keys """
        return []

    def pop(self, k, d=None): # real signature unknown; restored from __doc__
        """ 获取并在字典中移除 """
        """
        D.pop(k[,d]) -> v, remove specified key and return the corresponding value.
        If key is not found, d is returned if given, otherwise KeyError is raised
        """
        pass

    def popitem(self): # real signature unknown; restored from __doc__
        """ 获取并在字典中移除 """
        """
        D.popitem() -> (k, v), remove and return some (key, value) pair as a
        2-tuple; but raise KeyError if D is empty.
        """
        pass

    def setdefault(self, k, d=None): # real signature unknown; restored from __doc__
        """ 如果key不存在,则创建,如果存在,则返回已存在的值且不修改 """
        """ D.setdefault(k[,d]) -> D.get(k,d), also set D[k]=d if k not in D """
        pass

    def update(self, E=None, **F): # known special case of dict.update
        """ 更新
            {'name':'alex', 'age': 18000}
            [('name','sbsbsb'),]
        """
        """
        D.update([E, ]**F) -> None.  Update D from dict/iterable E and F.
        If E present and has a .keys() method, does:     for k in E: D[k] = E[k]
        If E present and lacks .keys() method, does:     for (k, v) in E: D[k] = v
        In either case, this is followed by: for k in F: D[k] = F[k]
        """
        pass

    def values(self): # real signature unknown; restored from __doc__
        """ 所有的值 """
        """ D.values() -> list of D's values """
        return []

    def viewitems(self): # real signature unknown; restored from __doc__
        """ 所有项,只是将内容保存至view对象中 """
        """ D.viewitems() -> a set-like object providing a view on D's items """
        pass

    def viewkeys(self): # real signature unknown; restored from __doc__
        """ D.viewkeys() -> a set-like object providing a view on D's keys """
        pass

    def viewvalues(self): # real signature unknown; restored from __doc__
        """ D.viewvalues() -> an object providing a view on D's values """
        pass

    def __cmp__(self, y): # real signature unknown; restored from __doc__
        """ x.__cmp__(y) <==> cmp(x,y) """
        pass

    def __contains__(self, k): # real signature unknown; restored from __doc__
        """ D.__contains__(k) -> True if D has a key k, else False """
        return False

    def __delitem__(self, y): # real signature unknown; restored from __doc__
        """ x.__delitem__(y) <==> del x[y] """
        pass

    def __eq__(self, y): # real signature unknown; restored from __doc__
        """ x.__eq__(y) <==> x==y """
        pass

    def __getattribute__(self, name): # real signature unknown; restored from __doc__
        """ x.__getattribute__('name') <==> x.name """
        pass

    def __getitem__(self, y): # real signature unknown; restored from __doc__
        """ x.__getitem__(y) <==> x[y] """
        pass

    def __ge__(self, y): # real signature unknown; restored from __doc__
        """ x.__ge__(y) <==> x>=y """
        pass

    def __gt__(self, y): # real signature unknown; restored from __doc__
        """ x.__gt__(y) <==> x>y """
        pass

    def __init__(self, seq=None, **kwargs): # known special case of dict.__init__
        """
        dict() -> new empty dictionary
        dict(mapping) -> new dictionary initialized from a mapping object's
            (key, value) pairs
        dict(iterable) -> new dictionary initialized as if via:
            d = {}
            for k, v in iterable:
                d[k] = v
        dict(**kwargs) -> new dictionary initialized with the name=value pairs
            in the keyword argument list.  For example:  dict(one=1, two=2)
        # (copied from class doc)
        """
        pass

    def __iter__(self): # real signature unknown; restored from __doc__
        """ x.__iter__() <==> iter(x) """
        pass

    def __len__(self): # real signature unknown; restored from __doc__
        """ x.__len__() <==> len(x) """
        pass

    def __le__(self, y): # real signature unknown; restored from __doc__
        """ x.__le__(y) <==> x<=y """
        pass

    def __lt__(self, y): # real signature unknown; restored from __doc__
        """ x.__lt__(y) <==> x<y """
        pass

    @staticmethod # known case of __new__
    def __new__(S, *more): # real signature unknown; restored from __doc__
        """ T.__new__(S, ...) -> a new object with type S, a subtype of T """
        pass

    def __ne__(self, y): # real signature unknown; restored from __doc__
        """ x.__ne__(y) <==> x!=y """
        pass

    def __repr__(self): # real signature unknown; restored from __doc__
        """ x.__repr__() <==> repr(x) """
        pass

    def __setitem__(self, i, y): # real signature unknown; restored from __doc__
        """ x.__setitem__(i, y) <==> x[i]=y """
        pass

    def __sizeof__(self): # real signature unknown; restored from __doc__
        """ D.__sizeof__() -> size of D in memory, in bytes """
        pass

    __hash__ = None

dict
dict

PS:循环,range,continue 和 break

 

其他

用户按照顺序循环可迭代对象中的内容,
PS:break、continue
 
1、for循环
用户按照顺序循环可迭代对象中的内容,
PS:break、continue
li = [11,22,33,44]
for item in li:
    print item

  

2、enumrate
为可迭代的对象添加序号
1 li = [11,22,33]
2 for k,v in enumerate(li, 1):
3     print(k,v)
3、range和xrange
指定范围,生成指定的数字
print range(110)
# 结果:[1, 2, 3, 4, 5, 6, 7, 8, 9]
 
print range(1102)
# 结果:[1, 3, 5, 7, 9]
 
print range(300-2)
# 结果:[30, 28, 26, 24, 22, 20, 18, 16, 14, 12, 10, 8, 6, 4, 2]  
 

练习题

 

一、元素分类

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}

二、查找
查找列表中元素,移除每个元素的空格,并查找以 a或A开头 并且以 c 结尾的所有元素。
    li = ["alec", " aric", "Alex", "Tony", "rain"]
    tu = ("alec", " aric", "Alex", "Tony", "rain") 
    dic = {'k1': "alex", 'k2': ' aric',  "k3": "Alex", "k4": "Tony"}
 
三、输出商品列表,用户输入序号,显示用户选中的商品
    商品 li = ["手机", "电脑", '鼠标垫', '游艇']
 
四、购物车

功能要求:

  • 要求用户输入总资产,例如:2000
  • 显示商品列表,让用户根据序号选择商品,加入购物车
  • 购买,如果商品总额大于总资产,提示账户余额不足,否则,购买成功。
  • 附加:可充值、某商品移除购物车
goods = [
    {"name": "电脑", "price": 1999},
    {"name": "鼠标", "price": 10},
    {"name": "游艇", "price": 20},
    {"name": "美女", "price": 998},
]

 五、用户交互,显示省市县三级联动的选择

dic = {
    "河北": {
        "石家庄": ["鹿泉", "藁城", "元氏"],
        "邯郸": ["永年", "涉县", "磁县"],
    }
    "河南": {
        ...
    }
    "山西": {
        ...
    }
 
}
原文地址:https://www.cnblogs.com/laixiaoyun/p/6092373.html