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  • Python开发【第三篇】：Python基本数据类型

 

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
 int
 
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
复制代码
class int(object):
    """
    int(x=0) -> int or long
    int(x, base=10) -> int or long
    
    Convert a number or string to an integer, or return 0 if no arguments
    are given.  If x is floating point, the conversion truncates towards zero.
    If x is outside the integer range, the function returns a long instead.
    
    If x is not a number or if base is given, then x must be a string or
    Unicode object representing an integer literal in the given base.  The
    literal can be preceded by '+' or '-' and be surrounded by whitespace.
    The base defaults to 10.  Valid bases are 0 and 2-36.  Base 0 means to
    interpret the base from the string as an integer literal.
    >>> int('0b100', base=0)
    4
    """
    def bit_length(self): 
        """ 返回表示该数字的时占用的最少位数 """
        """
        int.bit_length() -> int
        
        Number of bits necessary to represent self in binary.
        >>> bin(37)
        '0b100101'
        >>> (37).bit_length()
        6
        """
        return 0

    def conjugate(self, *args, **kwargs): # real signature unknown
        """ 返回该复数的共轭复数 """
        """ Returns self, the complex conjugate of any int. """
        pass

    def __abs__(self):
        """ 返回绝对值 """
        """ x.__abs__() <==> abs(x) """
        pass

    def __add__(self, y):
        """ x.__add__(y) <==> x+y """
        pass

    def __and__(self, y):
        """ x.__and__(y) <==> x&y """
        pass

    def __cmp__(self, y): 
        """ 比较两个数大小 """
        """ x.__cmp__(y) <==> cmp(x,y) """
        pass

    def __coerce__(self, y):
        """ 强制生成一个元组 """ 
        """ x.__coerce__(y) <==> coerce(x, y) """
        pass

    def __divmod__(self, y): 
        """ 相除，得到商和余数组成的元组 """ 
        """ x.__divmod__(y) <==> divmod(x, y) """
        pass

    def __div__(self, y): 
        """ x.__div__(y) <==> x/y """
        pass

    def __float__(self): 
        """ 转换为浮点类型 """ 
        """ x.__float__() <==> float(x) """
        pass

    def __floordiv__(self, y): 
        """ x.__floordiv__(y) <==> x//y """
        pass

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

    def __getattribute__(self, name): 
        """ x.__getattribute__('name') <==> x.name """
        pass

    def __getnewargs__(self, *args, **kwargs): # real signature unknown
        """ 内部调用 __new__方法或创建对象时传入参数使用 """ 
        pass

    def __hash__(self): 
        """如果对象object为哈希表类型，返回对象object的哈希值。哈希值为整数。在字典查找中，哈希值用于快速比较字典的键。两个数值如果相等，则哈希值也相等。"""
        """ x.__hash__() <==> hash(x) """
        pass

    def __hex__(self): 
        """ 返回当前数的 十六进制 表示 """ 
        """ x.__hex__() <==> hex(x) """
        pass

    def __index__(self): 
        """ 用于切片，数字无意义 """
        """ x[y:z] <==> x[y.__index__():z.__index__()] """
        pass

    def __init__(self, x, base=10): # known special case of int.__init__
        """ 构造方法，执行 x = 123 或 x = int(10) 时，自动调用，暂时忽略 """ 
        """
        int(x=0) -> int or long
        int(x, base=10) -> int or long
        
        Convert a number or string to an integer, or return 0 if no arguments
        are given.  If x is floating point, the conversion truncates towards zero.
        If x is outside the integer range, the function returns a long instead.
        
        If x is not a number or if base is given, then x must be a string or
        Unicode object representing an integer literal in the given base.  The
        literal can be preceded by '+' or '-' and be surrounded by whitespace.
        The base defaults to 10.  Valid bases are 0 and 2-36.  Base 0 means to
        interpret the base from the string as an integer literal.
        >>> int('0b100', base=0)
        4
        # (copied from class doc)
        """
        pass

    def __int__(self): 
        """ 转换为整数 """ 
        """ x.__int__() <==> int(x) """
        pass

    def __invert__(self): 
        """ x.__invert__() <==> ~x """
        pass

    def __long__(self): 
        """ 转换为长整数 """ 
        """ x.__long__() <==> long(x) """
        pass

    def __lshift__(self, y): 
        """ x.__lshift__(y) <==> x<<y """
        pass

    def __mod__(self, y): 
        """ x.__mod__(y) <==> x%y """
        pass

    def __mul__(self, y): 
        """ x.__mul__(y) <==> x*y """
        pass

    def __neg__(self): 
        """ x.__neg__() <==> -x """
        pass

    @staticmethod # known case of __new__
    def __new__(S, *more): 
        """ T.__new__(S, ...) -> a new object with type S, a subtype of T """
        pass

    def __nonzero__(self): 
        """ x.__nonzero__() <==> x != 0 """
        pass

    def __oct__(self): 
        """ 返回改值的 八进制 表示 """ 
        """ x.__oct__() <==> oct(x) """
        pass

    def __or__(self, y): 
        """ x.__or__(y) <==> x|y """
        pass

    def __pos__(self): 
        """ x.__pos__() <==> +x """
        pass

    def __pow__(self, y, z=None): 
        """ 幂，次方 """ 
        """ x.__pow__(y[, z]) <==> pow(x, y[, z]) """
        pass

    def __radd__(self, y): 
        """ x.__radd__(y) <==> y+x """
        pass

    def __rand__(self, y): 
        """ x.__rand__(y) <==> y&x """
        pass

    def __rdivmod__(self, y): 
        """ x.__rdivmod__(y) <==> divmod(y, x) """
        pass

    def __rdiv__(self, y): 
        """ x.__rdiv__(y) <==> y/x """
        pass

    def __repr__(self): 
        """转化为解释器可读取的形式 """
        """ x.__repr__() <==> repr(x) """
        pass

    def __str__(self): 
        """转换为人阅读的形式，如果没有适于人阅读的解释形式的话，则返回解释器课阅读的形式"""
        """ x.__str__() <==> str(x) """
        pass

    def __rfloordiv__(self, y): 
        """ x.__rfloordiv__(y) <==> y//x """
        pass

    def __rlshift__(self, y): 
        """ x.__rlshift__(y) <==> y<<x """
        pass

    def __rmod__(self, y): 
        """ x.__rmod__(y) <==> y%x """
        pass

    def __rmul__(self, y): 
        """ x.__rmul__(y) <==> y*x """
        pass

    def __ror__(self, y): 
        """ x.__ror__(y) <==> y|x """
        pass

    def __rpow__(self, x, z=None): 
        """ y.__rpow__(x[, z]) <==> pow(x, y[, z]) """
        pass

    def __rrshift__(self, y): 
        """ x.__rrshift__(y) <==> y>>x """
        pass

    def __rshift__(self, y): 
        """ x.__rshift__(y) <==> x>>y """
        pass

    def __rsub__(self, y): 
        """ x.__rsub__(y) <==> y-x """
        pass

    def __rtruediv__(self, y): 
        """ x.__rtruediv__(y) <==> y/x """
        pass

    def __rxor__(self, y): 
        """ x.__rxor__(y) <==> y^x """
        pass

    def __sub__(self, y): 
        """ x.__sub__(y) <==> x-y """
        pass

    def __truediv__(self, y): 
        """ x.__truediv__(y) <==> x/y """
        pass

    def __trunc__(self, *args, **kwargs): 
        """ 返回数值被截取为整形的值，在整形中无意义 """
        pass

    def __xor__(self, y): 
        """ x.__xor__(y) <==> x^y """
        pass

    denominator = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default
    """ 分母 = 1 """
    """the denominator of a rational number in lowest terms"""

    imag = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default
    """ 虚数，无意义 """
    """the imaginary part of a complex number"""

    numerator = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default
    """ 分子 = 数字大小 """
    """the numerator of a rational number in lowest terms"""

    real = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default
    """ 实属，无意义 """
    """the real part of a complex number"""
复制代码
2、布尔值
2、布尔值
　　真或假
　　1 或 0
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
4、列表
创建列表：
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name_list = ['alex', 'seven', 'eric']
或
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
5、元祖
创建元祖：
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ages = (11, 22, 33, 44, 55)
或
ages = tuple((11, 22, 33, 44, 55))
基本操作：
  • 索引
  • 切片
  • 循环
  • 长度
  • 包含
6、字典（无序）
创建字典：
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person = {"name": "mr.wu", 'age': 18}
或
person = dict({"name": "mr.wu", 'age': 18})

常用操作：

  • 索引
  • 新增
  • 删除
  • 键、值、键值对
  • 循环
  • 长度
PS：循环，range，continue 和 break

其他

1、for循环
用户按照顺序循环可迭代对象中的内容，
PS：break、continue
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li = [11,22,33,44]
for item in li:
    print item
2、enumrate
为可迭代的对象添加序号
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li = [11,22,33]
for k,v in enumerate(li, 1):
    print(k,v)
3、range和xrange
指定范围，生成指定的数字
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print range(1, 10)
# 结果：[1, 2, 3, 4, 5, 6, 7, 8, 9]
 
print range(1, 10, 2)
# 结果：[1, 3, 5, 7, 9]
 
print range(30, 0, -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
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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

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dic = {
    "河北": {
        "石家庄": ["鹿泉", "藁城", "元氏"],
        "邯郸": ["永年", "涉县", "磁县"],
    }
    "河南": {
        ...
    }
    "山西": {
        ...
    }
 
}
 

出处：https://www.cnblogs.com/weiman3389/p/6222972.html

　　



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