初识python第二天

Posted 2020-08-09

整理Python常见数据类型内置函数的使用方法如下：

一.int

首先我们来查看一下int包含了哪些函数

1 #python3.x
2 print(dir(int))
3 #[‘__abs__‘, ‘__add__‘, ‘__and__‘, ‘__bool__‘, ‘__ceil__‘, ‘__class__‘, ‘__delattr__‘, ‘__dir__‘, ‘__divmod__‘, ‘__doc__‘, ‘__eq__‘, ‘__float__‘, ‘__floor__‘, ‘__floordiv__‘, ‘__format__‘, ‘__ge__‘, ‘__getattribute__‘, ‘__getnewargs__‘, ‘__gt__‘, ‘__hash__‘, ‘__index__‘, ‘__init__‘, ‘__init_subclass__‘, ‘__int__‘, ‘__invert__‘, ‘__le__‘, ‘__lshift__‘, ‘__lt__‘, ‘__mod__‘, ‘__mul__‘, ‘__ne__‘, ‘__neg__‘, ‘__new__‘, ‘__or__‘, ‘__pos__‘, ‘__pow__‘, ‘__radd__‘, ‘__rand__‘, ‘__rdivmod__‘, ‘__reduce__‘, ‘__reduce_ex__‘, ‘__repr__‘, ‘__rfloordiv__‘, ‘__rlshift__‘, ‘__rmod__‘, ‘__rmul__‘, ‘__ror__‘, ‘__round__‘, ‘__rpow__‘, ‘__rrshift__‘, ‘__rshift__‘, ‘__rsub__‘, ‘__rtruediv__‘, ‘__rxor__‘, ‘__setattr__‘, ‘__sizeof__‘, ‘__str__‘, ‘__sub__‘, ‘__subclasshook__‘, ‘__truediv__‘, ‘__trunc__‘, ‘__xor__‘, ‘bit_length‘, ‘conjugate‘, ‘denominator‘, ‘from_bytes‘, ‘imag‘, ‘numerator‘, ‘real‘, ‘to_bytes‘]
4 
5 #python2.x
6 dir(int)
7 #[‘__abs__‘, ‘__add__‘, ‘__and__‘, ‘__class__‘, ‘__cmp__‘, ‘__coerce__‘, ‘__delattr__‘, ‘__div__‘, ‘__divmod__‘, ‘__doc__‘, ‘__float__‘, ‘__floordiv__‘, ‘__format__‘, ‘__getattribute__‘, ‘__getnewargs__‘, ‘__hash__‘, ‘__hex__‘, ‘__index__‘, ‘__init__‘, ‘__int__‘, ‘__invert__‘, ‘__long__‘, ‘__lshift__‘, ‘__mod__‘, ‘__mul__‘, ‘__neg__‘, ‘__new__‘, ‘__nonzero__‘, ‘__oct__‘, ‘__or__‘, ‘__pos__‘, ‘__pow__‘, ‘__radd__‘, ‘__rand__‘, ‘__rdiv__‘, ‘__rdivmod__‘, ‘__reduce__‘, ‘__reduce_ex__‘, ‘__repr__‘, ‘__rfloordiv__‘, ‘__rlshift__‘, ‘__rmod__‘, ‘__rmul__‘, ‘__ror__‘, ‘__rpow__‘, ‘__rrshift__‘, ‘__rshift__‘, ‘__rsub__‘, ‘__rtruediv__‘, ‘__rxor__‘, ‘__setattr__‘, ‘__sizeof__‘, ‘__str__‘, ‘__sub__‘, ‘__subclasshook__‘, ‘__truediv__‘, ‘__trunc__‘, ‘__xor__‘, ‘bit_length‘, ‘conjugate‘, ‘denominator‘, ‘imag‘, ‘numerator‘, ‘real‘]

 1 #__abs__()  绝对值    正数的绝对值是它本身。负数的绝对值是它的相反数。0的绝对值还是0
 2 
 3 num = 1
 4 result = num.__abs__()
 5 print(result)   #输出打印结果  1
 6 
 7 
 8 
 9 num = -1
10 result = num.__abs__()
11 print(result)    #输出打印结果  1

__abs__绝对值

1 num = 1
2 result = num.__add__(3)
3 print(result)
4 
5 #self+value  两个对象相加

__add__加法

 1 num = 6
 2 result = num.__and__(8)
 3 print(result)
 4 
 5 #输出打印结果  0
 6 
 7 # 0 0 0 0 0 1 1 0    6
 8 # 0 0 0 0 1 0 0 0    8
 9 
10 #相同位为1则为1，由于没有相同位，所以6&8结果为0
11 
12 
13 num = 6
14 result = num.__and__(4)
15 print(result)
16 #输出打印结  4
17 # 0 0 0 0 0 1 1 0
18 # 0 0 0 0 0 1 0 0
19 #如果相同位为1，就输出二进制对应的十进制数

__and__与&运算