Built-in methods:
1. ABS () #取绝对值;
>>> ABS (-11)
11
>>> ABS (11)
11
2. All #非0即真 to ensure that all elements are true;
>>> all ([0,-5, 3])
False
>>> all ([1,-5, 3])
True
3. Any #非0即真 to ensure that an element is true;
>>> any ([0,-5, 3])
True
>>> any ([1,-5, 3])
True
>>> any ([0,0])
False
4. ASCII () #将内存对象转变为一个可打印的字符形式
>>> ASCII ("ABCD")
"' ABCD '"
>>> ASCII ("abcd111")
"' abcd111 '"
>>> ASCII (1)
' 1 '
>>> ASCII ([up])
' [1, 2] '
5. Bin () #将十进制数字转换二进制
>>> Bin (8)
' 0b1000 '
>>> Bin (19)
' 0b10011 '
>>>
6. BOOL (): #判断是否真, empty list, etc. false false
>>> bool ([])
False
>>> bool ([up])
True
>>>
7. ByteArray () #把字符变成asscii可以更改;
>>> B = ByteArray ("ABDCD", encoding= "Utf-8")
>>>
>>> print (b[0])
97
>>> print (b[1])
98
>>> b[1]=100
>>> print (b)
ByteArray (b ' ADDCD ')
A = bytes ("ABDCD")
>>> A
B ' ABDCD
8. chr () #将ascii值转为对应的字符.
>>> Chr (90)
Z
9. Ord () #将字符转为ascii
>>> Ord ("a")
97
>>> Ord ("Z")
90
Complie () #简单的编译反执行. can use exec can execute string source code;
>>> code = "For I in Range":p rint (i) "
>>> Code
' For I in Range ':p rint (i) '
>>>
>>> Compile (Code, "", "exec")
<code object <module> at 0x00b540d0, file "", Line 1>
>>>
>>> c = Compile (code, "", "exec")
>>> EXEC (c)
0
1
2
3
4
5
6
7
8
9
>>>
Dir () #查看对象的方法:
>>> dir ({})
[' __class__ ', ' __contains__ ', ' __delattr__ ', ' __delitem__ ', ' __dir__ ', ' __doc__ ', ' __eq__ ', ' __format__ ', ' __ge__ ', ' __ getattribute__ ', ' __getitem__ ', ' __gt__ ', ' __hash__ ', ' __init__ ', ' __init_subclass__ ', ' __iter__ ', ' __le__ ', ' __len__ ' , ' __lt__ ', ' __ne__ ', ' __new__ ', ' __reduce__ ', ' __reduce_ex__ ', ' __repr__ ', ' __setattr__ ', ' __setitem__ ', ' __sizeof__ ', ' __str__ ', ' __subclasshook__ ', ' clear ', ' copy ', ' Fromkeys ', ' get ', ' items ', ' Keys ', ' Pop ', ' Popitem ', ' setdefault ', ' UPDA ' Te ', ' Values ']
>>> dir ([])
[' __add__ ', ' __class__ ', ' __contains__ ', ' __delattr__ ', ' __delitem__ ', ' __dir__ ', ' __doc__ ', ' __eq__ ', ' __format__ ', ' _ _ge__ ', ' __getattribute__ ', ' __getitem__ ', ' __gt__ ', ' __hash__ ', ' __iadd__ ', ' __imul__ ', ' __init__ ', ' __init_subclass_ ' _ ', ' __iter__ ', ' __le__ ', ' __len__ ', ' __lt__ ', ' __mul__ ', ' __ne__ ', ' __new__ ', ' __reduce__ ', ' __reduce_ex__ ', ' __repr__ ' , ' __reversed__ ', ' __rmul__ ', ' __setattr__ ', ' __setitem__ ', ' __sizeof__ ', ' __str__ ', ' __subclasshook__ ', ' Append ', ' Clear ', ' copy ', ' Count ', ' extend ', ' index ', ' Insert ', ' pop ', ' remove ', ' reverse ', ' sort ']
>>>
Divmod () #返回商和余数
>>> Divmod (5,1)
(5, 0)
>>> Divmod (5,2)
(2, 1)
>>> Divmod (5,3)
(1, 2)
>>>
Enumerate (): #
>>> sersons = ["Spring", "Summer", "Autron", "Wintor"]
>>>
>>> List (Enumerate (sersons))
[(0, ' Spring '), (1, ' Summer '), (2, ' Autron '), (3, ' wintor ')]
>>>
>>> List (Enumerate (sersons, start=1))
[(1, ' Spring '), (2, ' Summer '), (3, ' Autron '), (4, ' wintor ')]
>>>
>>>
>>> for K,v in enumerate (sersons, start=1):p rint ("%d--%s"% (k, v))
...
1--spring
2--summer
3--autron
4--wintor
>>>
Eval () #将字符串转为数据类型, no statement, EXEC with statement
>>> x = "[1,2,3,4]"
>>> x
' [1,2,3,4] '
>>>
>>> X[0]
‘[‘
>>>
>>> y = eval (x)
>>> y
[1, 2, 3, 4]
>>> Y[0]
1
>>>
. EXEC () # Execute string source code
>>> x = "For I in Range":p rint (i) "
>>> x
' For I in Range ':p rint (i) '
>>>
>>>
>>> EXEC (x)
0
1
2
3
4
5
6
7
8
9
>>>
Filter (): #按条件进行过滤
>>> x = filter (lambda n:n>5, Range (10))
>>> for I in X:print (i)
...
6
7
8
9
Take the following values out to the front processing
>>> x = map (lambda n:n*n, Range) #按照范围的输出, equivalent to: x = [Lambda n:n*n for I in range (10)]
>>> for I in X:print (i)
...
0
1
4
9
16
25
36
49
64
81
anonymous function: can only handle March operations
>>> Lambda N:print (n)
<function <lambda> at 0x0368bdb0>
>>>
>>> (lambda n:print (n)) (5)
5
>>>
>>> X=lambda n:print (n)
>>> x (5)
5
>>> Lambda m:m*2
<function <lambda> at 0x03716198>
>>> Y=lambda m:m*2
>>> y (5)
10
>>>
>>> z = Lambda N:3 if n<4 else n
>>> Z (2)
3
>>> Z (5)
5
Frozenset () #集合冻结, cannot be modified after
>>> A=set ([12,2,12,12,12,12])
>>> A
{2, 12}
>>> A.add (13)
>>> A
{2, 12, 13}
>>>
>>> B = Frozenset (a)
>>> b
Frozenset ({2, 12, 13})
>>>
>>>
>>> B.add (3)
Traceback (most recent):
File "<stdin>", line 1, in <module>
Attributeerror: ' Frozenset ' object has no attribute ' add '
>>>
Globals () #返回整个程序所有的全局变量值:
>>> Globals ()
{' __name__ ': ' __main__ ', ' __doc__ ': None, ' __package__ ': None, ' __loader__ ': <class ' _frozen_importlib. Builtinimporter ', ' __spec__ ': None, ' __annotations__ ': {}, ' __builtins__ ': <module ' builtins ' (built-in);, ' Iterable ': <class ' collections.abc.Iterable ', ' Iterator ': <class ' collections.abc.Iterator ', ' X ': < Map object at 0x00b56030>, ' a ': {2, +,--}, ' B ': Frozenset ({2, B, D}), ' Code ': ' For I in Range ':p rint (i) ', ' C ': & Lt;code object <module> at 0x00b54128, file "", line 1>, ' I ': Bayi, ' sersons ': [' Spring ', ' Summer ', ' Autron ', ' Wint or '], ' K ': 4, ' V ': ' wintor ', ' y ': <function <lambda> at 0x036ab6a8>, ' z ': <function <lambda> at 0x037 16150>}
>>>
Hash () # returns the hash value;
>>> Hash ("1")
-585053941
>>>
>>> Hash ("QWQW")
1784621666
>>>
Hex () #抓16进制
>>> Hex (100)
' 0x64 '
>>> Hex (15)
' 0xf '
>>>
Oct () #转为8进制
>>> Oct (10)
' 0o12 '
Locals () #打印本地变量;
>>> locals ()
{' __name__ ': ' __main__ ', ' __doc__ ': None, ' __package__ ': None, ' __loader__ ': <class ' _frozen_importlib. Builtinimporter ', ' __spec__ ': None, ' __annotations__ ': {}, ' __builtins__ ': <module ' builtins ' (built-in);, ' Iterable ': <class ' collections.abc.Iterable ', ' Iterator ': <class ' collections.abc.Iterator ', ' X ': < Map object at 0x00b56030>, ' a ': {2, +,--}, ' B ': Frozenset ({2, B, D}), ' Code ': ' For I in Range ':p rint (i) ', ' C ': & Lt;code object <module> at 0x00b54128, file "", line 1>, ' I ': Bayi, ' sersons ': [' Spring ', ' Summer ', ' Autron ', ' Wint or '], ' K ': 4, ' V ': ' wintor ', ' y ': <function <lambda> at 0x036ab6a8>, ' z ': <function <lambda> at 0x037 16150>}
>>>
Max (): #返回最大值
>>> Max ([1,2,3,4,5])
5 23. Min (): #返回最小值
>>> min ([1,2,3,4,5])
1
Pow (x, y) #返回多次幂, x y-square
>>> Pow (2,2)
4
>>> Pow (2,3)
8
Range (Start,stop,step) 26. Repr () #用字符串表示一个对对象:
Reversed (seq) #反转
Round () #浮点数按照规定四舍五入舍弃,
>>> Round (1.232442)
1
>>> Round (1.232442,2)
1.23
>>> Round (1.237442,2)
1.24
>>>
ID () #取内存id值
>>> ID ("1")
56589120
>>> ID ("a")
56501888
Sorted (Iterable[,key][,reverse]) #排序
>>> a = {5:1,9:2,1:3,8:4,3:9}
>>>
>>> Sorted (a)
[1, 3, 5, 8, 9]
>>> Sorted (A.items ())
[(1, 3), (3, 9), (5, 1), (8, 4), (9, 2)]
>>> Sorted (A.items (), Key=lambda x:x[1])
[(5, 1), (9, 2), (1, 3), (8, 4), (3, 9)]
>>> A.items () #将字典转化为列表.
Dict_items ([(5, 1), (9, 2), (1, 3), (8, 4), (3, 9)])
>>>
>>> List (a)
[5, 9, 1, 8, 3]
SUM (Iterable[,start]) #求和, start is the sum initial value
>>> sum ([1, 3, 5, 8, 9])
26
>>> sum ([1, 3, 5, 8, 9],3)
29
>>> sum ([1, 3, 5, 8, 9],30)
56
Tuple (iterable): #转化为元组
>>> tuple ([1, 3, 5, 8, 9])
(1, 3, 5, 8, 9)
A. zip () #中文就是拉链的意思 that corresponds
>>> a = (1, 3, 5, 8, 9)
>>> B = ("A", "B", "C", "D", "E")
>>>
>>> Zip (A, B)
<zip Object at 0x00b53990>
>>> for n in Zip (A, B):
... print (n)
...
(1, ' a ')
(3, ' B ')
(5, ' C ')
(8, ' d ')
(9, ' e ')
>>>
__import__ ("module name") #只知道模块名时导入模块就方法:
Anatomy of Python's built-in functions
