Built-in Functions | ||||||
---|---|---|---|---|---|---|
abs() | dict() | help() | min() | setattr() | all() | dir() |
hex() | next() | slice() | any() | pmod() | id() | object() |
sorted() | ascii() | enumerate() | input() | oct() | staticmethod() | bin() |
eval() | int() | open() | str() | bool() | exec() | isinstance() |
ord() | sum() | bytearray() | filter() | issubclass() | pow() | super() |
bytes() | float() | iter() | print() | tuple() | callable() | format() |
len() | property() | type() | chr() | frozenset() | list() | range() |
vars() | classmethod() | getattr() | locals() | repr() | zip() | compile() |
globals() | map() | reversed() | __import__() | complex() | hasattr() | max() |
round() | delattr() | hash() | memoryview() | set() |
官方介绍:#
abs(x)
返回数字的绝对值,参数可以是整数或浮点数,如果参数是复数,则返回其大小。
# 如果参数是复数,则返回其大小。 >>> abs(-25) 25 >>> abs(25) 25
all(iterable)
all()会循环括号内的每一个元素,如果括号内的所有元素都是真的,或者如果iterable为空,则返回
True
,如果有一个为假的那么就返回False
>>> all([]) True >>> all([1,2,3]) True >>> all([1,2,""]) False # 如果有一个为假,则都为假 >>> all([1,2,None]) False
假的参数有:False
、0
、None
、""
、[]
、()
、{}
等,查看一个元素是否为假可以使用bool进行查看。
any(iterable)
循环元素,如果有一个元素为真,那么就返回True,否则就返回False
>>> any([0,1]) True >>> any([0]) False
ascii(object)
在对象的类中寻找
__repr__
方法,获取返回值
>>> class Foo: ... def __repr_(self): ... return "hello" ... >>> obj = Foo() >>> r = ascii(obj) >>> print(r) # 返回的是一个可迭代的对象 <__main__.Foo object at 0x000001FDEE13D320>
bin(x)
将整数x转换为二进制字符串,如果x不为Python中int类型,x必须包含方法__index__()
并且返回值为integer
# 返回一个整数的二进制 >>> bin(999) &#39;0b1111100111&#39;
# 非整型的情况,必须包含__index__()方法切返回值为integer的类型 >>> class myType: ... def __index__(self): ... return 35 ... >>> myvar = myType() >>> bin(myvar) &#39;0b100011&#39;
bool([x])
查看一个元素的布尔值,非真即假
>>> bool(0) False >>> bool(1) True >>> bool([1]) True >>> bool([10]) True
bytearray([source [, encoding [, errors]]])
返回一个byte数组,Bytearray类型是一个可变的序列,并且序列中的元素的取值范围为 [0 ,255]。
source参数:
如果source为整数,则返回一个长度为source的初始化数组;
如果source为字符串,则按照指定的encoding将字符串转换为字节序列;
如果source为可迭代类型,则元素必须为[0 ,255]中的整数;
如果source为与buffer接口一致的对象,则此对象也可以被用于初始化bytearray.。
>>> bytearray(3) bytearray(b&#39;\x00\x00\x00&#39;)
bytes([source[, encoding[, errors]]])
>>> bytes("asdasd",encoding="utf-8") b&#39;asdasd&#39;
callable(object)
返回一个对象是否可以被执行
>>> def func(): ... return 123 ... >>> callable(func) True >>> func = 123 >>> callable(func) False
chr(i)
返回一个数字在ASCII编码中对应的字符,取值范围256个
>>> chr(66) &#39;B&#39; >>> chr(5) &#39;\x05&#39; >>> chr(55) &#39;7&#39; >>> chr(255) &#39;\xff&#39; >>> chr(25) &#39;\x19&#39; >>> chr(65) &#39;A&#39;
classmethod(function)
返回函数的类方法
compile(source, filename, mode, flags=0, dont_inherit=False, optimize=-1)
把字符串编译成python可执行的代码
>>> str = "for i in range(0,10): print(i)" >>> c = compile(str,&#39;&#39;,&#39;exec&#39;) >>> exec(c) 0 1 2 3 4 5 6 7 8 9
complex([real[, imag]])
创建一个值为real + imag * j的复数或者转化一个字符串或数为复数。如果第一个参数为字符串,则不需要指定第二个参数
>>> complex(1, 2) (1+2j) # 数字 >>> complex(1) (1+0j) # 当做字符串处理 >>> complex("1") (1+0j) # 注意:这个地方在“+”号两边不能有空格,也就是不能写成"1 + 2j",应该是"1+2j",否则会报错 >>> complex("1+2j") (1+2j)
delattr(object, name)
删除对象的属性值
>>> class cls: ... @classmethod ... def echo(self): ... print(&#39;CLS&#39;) ... >>> cls.echo() CLS >>> delattr(cls, &#39;echo&#39;) >>> cls.echo() Traceback (most recent call last): File "", line 1, in AttributeError: type object &#39;cls&#39; has no attribute &#39;echo&#39;
dict(**kwarg)
创建一个数据类型为字典
>>> dic = dict({"k1":"123","k2":"456"}) >>> dic {&#39;k1&#39;: &#39;123&#39;, &#39;k2&#39;: &#39;456&#39;}
dir([object])
返回一个对象中中的所有方法
>>> dir(str) [&#39;__add__&#39;, &#39;__class__&#39;, &#39;__contains__&#39;, &#39;__delattr__&#39;, &#39;__dir__&#39;, &#39;__doc__&#39;, &#39;__eq__&#39;, &#39;__format__&#39;, &#39;__ge__&#39;, &#39;__getattribute__&#39;, &#39;__getitem__&#39;, &#39;__getnewargs__&#39;, &#39;__gt__&#39;, &#39;__hash__&#39;, &#39;__init__&#39;, &#39;__iter__&#39;, &#39;__le__&#39;, &#39;__len__&#39;, &#39;__lt__&#39;, &#39;__mod__&#39;, &#39;__mul__&#39;, &#39;__ne__&#39;, &#39;__new__&#39;, &#39;__reduce__&#39;, &#39;__reduce\_ex__&#39;, &#39;__repr__&#39;, &#39;__rmod__&#39;, &#39;__rmul__&#39;, &#39;__setattr__&#39;, &#39;__sizeof__&#39;, &#39;__str__&#39;, &#39;__subclasshook__&#39;, &#39;capitalize&#39;, &#39;casefold&#39;, &#39;center&#39;, &#39;count&#39;, &#39;encode&#39;, &#39;endswith&#39;, &#39;expandtabs&#39;, &#39;find&#39;, &#39;format&#39;, &#39;format_map&#39;, &#39;index&#39;, &#39;isalnum&#39;, &#39;isalpha&#39;, &#39;isdecimal&#39;, &#39;isdigit&#39;, &#39;isidentifier&#39;, &#39;islower&#39;, &#39;isnumeric&#39;, &#39;isprintable&#39;, &#39;isspace&#39;, &#39;istitle&#39;, &#39;isupper&#39;, &#39;join&#39;, &#39;ljust&#39;, &#39;lower&#39;, &#39;lstrip&#39;, &#39;maketrans&#39;, &#39;partition&#39;, &#39;replace&#39;, &#39;rfind&#39;, &#39;rindex&#39;, &#39;rjust&#39;, &#39;rpartition&#39;, &#39;rsplit&#39;, &#39;rstrip&#39;, &#39;split&#39;, &#39;splitlines&#39;, &#39;startswith&#39;, &#39;strip&#39;, &#39;swapcase&#39;, &#39;title&#39;, &#39;translate&#39;, &#39;upper&#39;, &#39;zfill&#39;]
pmod(a, b)
返回的是a//b(除法取整)以及a对b的余数,返回结果类型为tuple
>>> pmod(10, 3) (3, 1)
enumerate(iterable, start=0)
为元素生成下标
>>> li = ["a","b","c"] >>> for n,k in enumerate(li): ... print(n,k) ... 0 a 1 b 2 c
eval(expression, globals=None, locals=None)
把一个字符串当作一个表达式去执行
>>> string = "1 + 3" >>> string &#39;1 + 3&#39; >>> eval(string) 4
exec(object[, globals[, locals]])
把字符串当作python代码执行
>>> exec("for n in range(5): print(n)") 0 1 2 3 4
filter(function, iterable)
筛选过滤,循环可迭代的对象,把迭代的对象当作函数的参数,如果符合条件就返回
True
,否则就返回False
>>> def func(x): ... if x == 11 or x == 22: ... return True ... >>> ret = filter(func,[11,22,33,44]) >>> for n in ret: ... print(n) ... 11 22
>>> list(filter((lambda x: x > 0),range(-5,5))) [1, 2, 3, 4]
float([x])
将整数和字符串转换成浮点数
>>> float("124") 124.0 >>> float("123.45") 123.45 >>> float("-123.34") -123.34
format(value[, format_spec])
字符串格式化
详键:#
frozenset([iterable])
frozenset是冻结的集合,它是不可变的,存在哈希值,好处是它可以作为字典的key,也可以作为其它集合的元素。缺点是一旦创建便不能更改,没有add,remove方法。
getattr(object, name[, default])
返回对象的命名属性的值,
name
必须是字符串,如果字符串是对象属性之一的名称,则结果是该属性的值。
globals()
获取或修改当前文件内的全局变量
>>> a = "12" >>> bsd = "54asd" >>> globals() {&#39;__doc__&#39;: None, &#39;a&#39;: &#39;12&#39;, &#39;__loader__&#39;:, &#39;bsd&#39;: &#39;54asd&#39;, &#39;__builtins__&#39;: , &#39;n&#39;: &#39;__doc__&#39;, &#39;__name__&#39;: &#39;__main__&#39;, &#39;__spec__&#39;: None, &#39;__package__&#39;: None}
hasattr(object, name)
参数是一个对象和一个字符串,如果字符串是对象的某个属性的名称,则结果为True,否则为False。
hash(object)
返回一个对象的hash值
>>> a = "asdadasdwqeq234sdfdf" >>> hash(a) 5390438057823015497
help([object])
查看一个类的所有详细方法,或者查看某个方法的使用详细信息
>>> help(list) Help on class list in module __builtin__: class list(object) | list() -> new empty list | list(iterable) -> new list initialized from iterable&#39;s items | | Methods defined here: | | __add__(...) | x.__add__(y) <==> x+y | | __contains__(...) | x.__contains__(y) <==> y in x | | __delitem__(...) | x.__delitem__(y) <==> del x[y] | | __delslice__(...) | x.__delslice__(i, j) <==> del x[i:j] | | Use of negative indices is not supported. ..........
hex(x)
获取一个数的十六进制
>>> hex(13) &#39;0xd&#39;
id(object)
返回一个对象的内存地址
>>> a = 123 >>> id(a) 1835400816
input([prompt])
交互式输入
>>> name = input("Pless your name: ") Pless your name: ansheng >>> print(name) ansheng
int(x, base=10)
获取一个数的十进制
>>> int("31") 31
也可以作为进制转换
>>> int(10) 10 >>> int(&#39;0b11&#39;,base=2) 3 >>> int(&#39;11&#39;,base=8) 9 >>> int(&#39;0xe&#39;,base=16) 14
isinstance(object, classinfo)
判断对象是否是这个类创建的
>>> li = [11,22,33] >>> isinstance(li,list) True
issubclass(class, classinfo)
查看一个对象是否为子类
iter(object[, sentinel])
创建一个可迭代的对象
>>> obj = iter([11,22,33,44]) >>> obj>>> for n in obj: ... print(n) ... 11 22 33 44
len(s)
查看一个对象的长度
>>> url="ansheng.me" >>> len(url) 10
list([iterable])
创建一个数据类型为列表
>>> li = list([11,22,33,44]) >>> li [11, 22, 33, 44]
locals()
返回当前作用域的局部变量,以字典形式输出
>>> func() >>> def func(): ... name="ansheng" ... print(locals()) ... >>> func() {&#39;name&#39;: &#39;ansheng&#39;}
map(function, iterable, ...)
对一个序列中的每一个元素都传到函数中执行并返回
>>> list(map((lambda x : x +10),[1,2,3,4])) [11, 12, 13, 14]
max(iterable, *[, key, default])
max(arg1, arg2, *args[, key])
取一个对象中的最大值
>>> li = list([11,22,33,44]) >>> li = [11,22,33,44] >>> max(li) 44
memoryview(obj)
返回对象obj的内存查看对象
>>> import struct >>> buf = struct.pack("i"*12, *list(range(12))) >>> x = memoryview(buf) >>> y = x.cast(&#39;i&#39;, shape=[2,2,3]) >>> print(y.tolist()) [[[0, 1, 2], [3, 4, 5]], [[6, 7, 8], [9, 10, 11]]]
min(iterable, *[, key, default])
min(arg1, arg2, *args[, key])
取一个对象中的最小值
>>> li = list([11,22,33,44]) >>> li = [11,22,33,44] >>> min(li) 11
next(iterator[, default])
每次只拿取可迭代对象的一个元素
>>> obj = iter([11,22,33,44]) >>> next(obj) 11 >>> next(obj) 22 >>> next(obj) 33 >>> next(obj) 44 >>> next(obj) # 如果没有可迭代的元素了就会报错 Traceback (most recent call last): File "", line 1, in StopIteration
object
返回一个新的无特征对象
oct(x)
获取一个字符串的八进制
>>> oct(13) &#39;0o15&#39;
open(file, mode=&#39;r&#39;, buffering=-1, encoding=None, errors=None, newline=None, closefd=True, opener=None)
文件操作的函数,用来做文件操作的
# 打开一个文件 - >>> f = open("a.txt","r")
ord(c)
把一个字母转换为ASCII对对应表中的数字
>>> ord("a") 97 >>> ord("t") 116
pow(x, y[, z])
返回一个数的N次方
>>> pow(2, 10) 1024 >>> pow(2, 20) 1048576
print(*objects, sep=&#39; &#39;, end=&#39;n&#39;, file=sys.stdout, flush=False)
打印输出
>>> print("hello word") hello word
property(fget=None, fset=None, fdel=None, doc=None)
range(start, stop[, step])
生成一个序列
>>> range(10) range(0, 10) >>> for n in range(5): ... print(n) ... 0 1 2 3 4
repr(object)
返回一个包含对象的可打印表示的字符串
>>> repr(111) &#39;111&#39; >>> repr(111.11) &#39;111.11&#39;
reversed(seq)
对一个对象的元素进行反转
>>> li = [1, 2, 3, 4] >>> reversed(li)>>> for n in reversed(li): ... print(n) ... 4 3 2 1
round(number[, ndigits])
四舍五入
>>> round(3.3) 3 >>> round(3.7) 4
set([iterable])
创建一个数据类型为集合
>>> varss = set([11,222,333]) >>> type(varss)
setattr(object, name, value)
为某个对象设置一个属性
slice(start, stop[, step])
元素的切片操作都是调用的这个方法
sorted(iterable, key)
为一个对象的元素进行排序
代码:
#!/usr/bin/env python # _*_ coding:utf-8 _*_ char=[&#39;赵&#39;,"123", "1", "25", "65","679999999999", "a","B","alex","c" ,"A", "_", "ᒲ",&#39;a钱&#39;,&#39;孙&#39;,&#39;李&#39;,"余", &#39;佘&#39;,"佗", "㽙", "铱", "钲钲㽙㽙㽙"] new_chat = sorted(char) print(new_chat) for i in new_chat: print(bytes(i, encoding=&#39;utf-8&#39;))
输出结果:
C:\Python35\python.exe F:/Python_code/Note/soretd.py [&#39;1&#39;, &#39;123&#39;, &#39;25&#39;, &#39;65&#39;, &#39;679999999999&#39;, &#39;A&#39;, &#39;B&#39;, &#39;_&#39;, &#39;a&#39;, &#39;alex&#39;, &#39;a钱&#39;, &#39;c&#39;, &#39;ᒲ&#39;, &#39;㽙&#39;, &#39;佗&#39;, &#39;佘&#39;, &#39;余&#39;, &#39;孙&#39;, &#39;李&#39;, &#39;赵&#39;, &#39;钲钲㽙㽙㽙&#39;, &#39;铱&#39;] b&#39;1&#39; b&#39;123&#39; b&#39;25&#39; b&#39;65&#39; b&#39;679999999999&#39; b&#39;A&#39; b&#39;B&#39; b&#39;_&#39; b&#39;a&#39; b&#39;alex&#39; b&#39;a\xe9\x92\xb1&#39; b&#39;c&#39; b&#39;\xe1\x92\xb2&#39; b&#39;\xe3\xbd\x99&#39; b&#39;\xe4\xbd\x97&#39; b&#39;\xe4\xbd\x98&#39; b&#39;\xe4\xbd\x99&#39; b&#39;\xe5\xad\x99&#39; b&#39;\xe6\x9d\x8e&#39; b&#39;\xe8\xb5\xb5&#39; b&#39;\xe9\x92\xb2\xe9\x92\xb2\xe3\xbd\x99\xe3\xbd\x99\xe3\xbd\x99&#39; b&#39;\xe9\x93\xb1&#39; Process finished with exit code 0
staticmethod(function)
返回函数的静态方法
str(object=b&#39;&#39;, encoding=&#39;utf-8&#39;, errors=&#39;strict&#39;)
字符串
>>> a = str(111) >>> type(a)
sum(iterable[, start])
求和
>>> sum([11,22,33]) 66
super([type[, object-or-type]])
执行父类的构造方法
tuple([iterable])
创建一个对象,数据类型为元组
>>> tup = tuple([11,22,33,44]) >>> type(tup)
type(object)
查看一个对象的数据类型
>>> a = 1 >>> type(a)>>> a = "str" >>> type(a)
vars([object])
查看一个对象里面有多少个变量
zip(*iterables)
将两个元素相同的序列转换为字典
>>> li1 = ["k1","k2","k3"] >>> li2 = ["a","b","c"] >>> d = dict(zip(li1,li2)) >>> d {&#39;k1&#39;: &#39;a&#39;, &#39;k2&#39;: &#39;b&#39;, &#39;k3&#39;: &#39;c&#39;}
__import__(name, globals=None, locals=None, fromlist=(), level=0)
导入模块,把导入的模块作为一个别名
生成一个六位的随机验证码,且包含数字,数字的位置随机
# 导入random模块 import random temp = "" for i in range(6): num = random.randrange(0,4) if num == 3 or num == 1: rad2 = random.randrange(0,10) temp = temp + str(rad2) else: rad1 = random.randrange(65,91) c1 = chr(rad1) temp = temp + c1 print(temp)
输出结果
C:\Python35\python.exe F:/Python_code/sublime/Day06/built_in.py 72TD11
原文链接
The Python interpreter has a number of functions and types built into it that are always available. They are listed here in alphabetical order.
Built-in Functions | ||||||
---|---|---|---|---|---|---|
abs() | dict() | help() | min() | setattr() | all() | dir() |
hex() | next() | slice() | any() | pmod() | id() | object() |
sorted() | ascii() | enumerate() | input() | oct() | staticmethod() | bin() |
eval() | int() | open() | str() | bool() | exec() | isinstance() |
ord() | sum() | bytearray() | filter() | issubclass() | pow() | super() |
bytes() | float() | iter() | print() | tuple() | callable() | format() |
len() | property() | type() | chr() | frozenset() | list() | range() |
vars() | classmethod() | getattr() | locals() | repr() | zip() | compile() |
globals() | map() | reversed() | __import__() | complex() | hasattr() | max() |
round() | delattr() | hash() | memoryview() | set() |
官方介绍:#
abs(x)
返回数字的绝对值,参数可以是整数或浮点数,如果参数是复数,则返回其大小。
# 如果参数是复数,则返回其大小。 >>> abs(-25) 25 >>> abs(25) 25
all(iterable)
all()会循环括号内的每一个元素,如果括号内的所有元素都是真的,或者如果iterable为空,则返回
True
,如果有一个为假的那么就返回False
>>> all([]) True >>> all([1,2,3]) True >>> all([1,2,""]) False # 如果有一个为假,则都为假 >>> all([1,2,None]) False
假的参数有:False
、0
、None
、""
、[]
、()
、{}
等,查看一个元素是否为假可以使用bool进行查看。
any(iterable)
循环元素,如果有一个元素为真,那么就返回True,否则就返回False
>>> any([0,1]) True >>> any([0]) False
ascii(object)
在对象的类中寻找
__repr__
方法,获取返回值
>>> class Foo: ... def __repr_(self): ... return "hello" ... >>> obj = Foo() >>> r = ascii(obj) >>> print(r) # 返回的是一个可迭代的对象 <__main__.Foo object at 0x000001FDEE13D320>
bin(x)
将整数x转换为二进制字符串,如果x不为Python中int类型,x必须包含方法__index__()
并且返回值为integer
# 返回一个整数的二进制 >>> bin(999) &#39;0b1111100111&#39;
# 非整型的情况,必须包含__index__()方法切返回值为integer的类型 >>> class myType: ... def __index__(self): ... return 35 ... >>> myvar = myType() >>> bin(myvar) &#39;0b100011&#39;
bool([x])
查看一个元素的布尔值,非真即假
>>> bool(0) False >>> bool(1) True >>> bool([1]) True >>> bool([10]) True
bytearray([source [, encoding [, errors]]])
返回一个byte数组,Bytearray类型是一个可变的序列,并且序列中的元素的取值范围为 [0 ,255]。
source参数:
如果source为整数,则返回一个长度为source的初始化数组;
如果source为字符串,则按照指定的encoding将字符串转换为字节序列;
如果source为可迭代类型,则元素必须为[0 ,255]中的整数;
如果source为与buffer接口一致的对象,则此对象也可以被用于初始化bytearray.。
>>> bytearray(3) bytearray(b&#39;\x00\x00\x00&#39;)
bytes([source[, encoding[, errors]]])
>>> bytes("asdasd",encoding="utf-8") b&#39;asdasd&#39;
callable(object)
返回一个对象是否可以被执行
>>> def func(): ... return 123 ... >>> callable(func) True >>> func = 123 >>> callable(func) False
chr(i)
返回一个数字在ASCII编码中对应的字符,取值范围256个
>>> chr(66) &#39;B&#39; >>> chr(5) &#39;\x05&#39; >>> chr(55) &#39;7&#39; >>> chr(255) &#39;\xff&#39; >>> chr(25) &#39;\x19&#39; >>> chr(65) &#39;A&#39;
classmethod(function)
返回函数的类方法
compile(source, filename, mode, flags=0, dont_inherit=False, optimize=-1)
把字符串编译成python可执行的代码
>>> str = "for i in range(0,10): print(i)" >>> c = compile(str,&#39;&#39;,&#39;exec&#39;) >>> exec(c) 0 1 2 3 4 5 6 7 8 9
complex([real[, imag]])
创建一个值为real + imag * j的复数或者转化一个字符串或数为复数。如果第一个参数为字符串,则不需要指定第二个参数
>>> complex(1, 2) (1+2j) # 数字 >>> complex(1) (1+0j) # 当做字符串处理 >>> complex("1") (1+0j) # 注意:这个地方在“+”号两边不能有空格,也就是不能写成"1 + 2j",应该是"1+2j",否则会报错 >>> complex("1+2j") (1+2j)
delattr(object, name)
删除对象的属性值
>>> class cls: ... @classmethod ... def echo(self): ... print(&#39;CLS&#39;) ... >>> cls.echo() CLS >>> delattr(cls, &#39;echo&#39;) >>> cls.echo() Traceback (most recent call last): File "", line 1, in AttributeError: type object &#39;cls&#39; has no attribute &#39;echo&#39;
dict(**kwarg)
创建一个数据类型为字典
>>> dic = dict({"k1":"123","k2":"456"}) >>> dic {&#39;k1&#39;: &#39;123&#39;, &#39;k2&#39;: &#39;456&#39;}
dir([object])
返回一个对象中中的所有方法
>>> dir(str) [&#39;__add__&#39;, &#39;__class__&#39;, &#39;__contains__&#39;, &#39;__delattr__&#39;, &#39;__dir__&#39;, &#39;__doc__&#39;, &#39;__eq__&#39;, &#39;__format__&#39;, &#39;__ge__&#39;, &#39;__getattribute__&#39;, &#39;__getitem__&#39;, &#39;__getnewargs__&#39;, &#39;__gt__&#39;, &#39;__hash__&#39;, &#39;__init__&#39;, &#39;__iter__&#39;, &#39;__le__&#39;, &#39;__len__&#39;, &#39;__lt__&#39;, &#39;__mod__&#39;, &#39;__mul__&#39;, &#39;__ne__&#39;, &#39;__new__&#39;, &#39;__reduce__&#39;, &#39;__reduce\_ex__&#39;, &#39;__repr__&#39;, &#39;__rmod__&#39;, &#39;__rmul__&#39;, &#39;__setattr__&#39;, &#39;__sizeof__&#39;, &#39;__str__&#39;, &#39;__subclasshook__&#39;, &#39;capitalize&#39;, &#39;casefold&#39;, &#39;center&#39;, &#39;count&#39;, &#39;encode&#39;, &#39;endswith&#39;, &#39;expandtabs&#39;, &#39;find&#39;, &#39;format&#39;, &#39;format_map&#39;, &#39;index&#39;, &#39;isalnum&#39;, &#39;isalpha&#39;, &#39;isdecimal&#39;, &#39;isdigit&#39;, &#39;isidentifier&#39;, &#39;islower&#39;, &#39;isnumeric&#39;, &#39;isprintable&#39;, &#39;isspace&#39;, &#39;istitle&#39;, &#39;isupper&#39;, &#39;join&#39;, &#39;ljust&#39;, &#39;lower&#39;, &#39;lstrip&#39;, &#39;maketrans&#39;, &#39;partition&#39;, &#39;replace&#39;, &#39;rfind&#39;, &#39;rindex&#39;, &#39;rjust&#39;, &#39;rpartition&#39;, &#39;rsplit&#39;, &#39;rstrip&#39;, &#39;split&#39;, &#39;splitlines&#39;, &#39;startswith&#39;, &#39;strip&#39;, &#39;swapcase&#39;, &#39;title&#39;, &#39;translate&#39;, &#39;upper&#39;, &#39;zfill&#39;]
pmod(a, b)
返回的是a//b(除法取整)以及a对b的余数,返回结果类型为tuple
>>> pmod(10, 3) (3, 1)
enumerate(iterable, start=0)
为元素生成下标
>>> li = ["a","b","c"] >>> for n,k in enumerate(li): ... print(n,k) ... 0 a 1 b 2 c
eval(expression, globals=None, locals=None)
把一个字符串当作一个表达式去执行
>>> string = "1 + 3" >>> string &#39;1 + 3&#39; >>> eval(string) 4
exec(object[, globals[, locals]])
把字符串当作python代码执行
>>> exec("for n in range(5): print(n)") 0 1 2 3 4
filter(function, iterable)
筛选过滤,循环可迭代的对象,把迭代的对象当作函数的参数,如果符合条件就返回
True
,否则就返回False
>>> def func(x): ... if x == 11 or x == 22: ... return True ... >>> ret = filter(func,[11,22,33,44]) >>> for n in ret: ... print(n) ... 11 22
>>> list(filter((lambda x: x > 0),range(-5,5))) [1, 2, 3, 4]
float([x])
将整数和字符串转换成浮点数
>>> float("124") 124.0 >>> float("123.45") 123.45 >>> float("-123.34") -123.34
format(value[, format_spec])
字符串格式化
详键:#
frozenset([iterable])
frozenset是冻结的集合,它是不可变的,存在哈希值,好处是它可以作为字典的key,也可以作为其它集合的元素。缺点是一旦创建便不能更改,没有add,remove方法。
getattr(object, name[, default])
返回对象的命名属性的值,
name
必须是字符串,如果字符串是对象属性之一的名称,则结果是该属性的值。
globals()
获取或修改当前文件内的全局变量
>>> a = "12" >>> bsd = "54asd" >>> globals() {&#39;__doc__&#39;: None, &#39;a&#39;: &#39;12&#39;, &#39;__loader__&#39;:, &#39;bsd&#39;: &#39;54asd&#39;, &#39;__builtins__&#39;: , &#39;n&#39;: &#39;__doc__&#39;, &#39;__name__&#39;: &#39;__main__&#39;, &#39;__spec__&#39;: None, &#39;__package__&#39;: None}
hasattr(object, name)
参数是一个对象和一个字符串,如果字符串是对象的某个属性的名称,则结果为True,否则为False。
hash(object)
返回一个对象的hash值
>>> a = "asdadasdwqeq234sdfdf" >>> hash(a) 5390438057823015497
help([object])
查看一个类的所有详细方法,或者查看某个方法的使用详细信息
>>> help(list) Help on class list in module __builtin__: class list(object) | list() -> new empty list | list(iterable) -> new list initialized from iterable&#39;s items | | Methods defined here: | | __add__(...) | x.__add__(y) <==> x+y | | __contains__(...) | x.__contains__(y) <==> y in x | | __delitem__(...) | x.__delitem__(y) <==> del x[y] | | __delslice__(...) | x.__delslice__(i, j) <==> del x[i:j] | | Use of negative indices is not supported. ..........
hex(x)
获取一个数的十六进制
>>> hex(13) &#39;0xd&#39;
id(object)
返回一个对象的内存地址
>>> a = 123 >>> id(a) 1835400816
input([prompt])
交互式输入
>>> name = input("Pless your name: ") Pless your name: ansheng >>> print(name) ansheng
int(x, base=10)
获取一个数的十进制
>>> int("31") 31
也可以作为进制转换
>>> int(10) 10 >>> int(&#39;0b11&#39;,base=2) 3 >>> int(&#39;11&#39;,base=8) 9 >>> int(&#39;0xe&#39;,base=16) 14
isinstance(object, classinfo)
判断对象是否是这个类创建的
>>> li = [11,22,33] >>> isinstance(li,list) True
issubclass(class, classinfo)
查看一个对象是否为子类
iter(object[, sentinel])
创建一个可迭代的对象
>>> obj = iter([11,22,33,44]) >>> obj>>> for n in obj: ... print(n) ... 11 22 33 44
len(s)
查看一个对象的长度
>>> url="ansheng.me" >>> len(url) 10
list([iterable])
创建一个数据类型为列表
>>> li = list([11,22,33,44]) >>> li [11, 22, 33, 44]
locals()
返回当前作用域的局部变量,以字典形式输出
>>> func() >>> def func(): ... name="ansheng" ... print(locals()) ... >>> func() {&#39;name&#39;: &#39;ansheng&#39;}
map(function, iterable, ...)
对一个序列中的每一个元素都传到函数中执行并返回
>>> list(map((lambda x : x +10),[1,2,3,4])) [11, 12, 13, 14]
max(iterable, *[, key, default])
max(arg1, arg2, *args[, key])
取一个对象中的最大值
>>> li = list([11,22,33,44]) >>> li = [11,22,33,44] >>> max(li) 44
memoryview(obj)
返回对象obj的内存查看对象
>>> import struct >>> buf = struct.pack("i"*12, *list(range(12))) >>> x = memoryview(buf) >>> y = x.cast(&#39;i&#39;, shape=[2,2,3]) >>> print(y.tolist()) [[[0, 1, 2], [3, 4, 5]], [[6, 7, 8], [9, 10, 11]]]
min(iterable, *[, key, default])
min(arg1, arg2, *args[, key])
取一个对象中的最小值
>>> li = list([11,22,33,44]) >>> li = [11,22,33,44] >>> min(li) 11
next(iterator[, default])
每次只拿取可迭代对象的一个元素
>>> obj = iter([11,22,33,44]) >>> next(obj) 11 >>> next(obj) 22 >>> next(obj) 33 >>> next(obj) 44 >>> next(obj) # 如果没有可迭代的元素了就会报错 Traceback (most recent call last): File "", line 1, in StopIteration
object
返回一个新的无特征对象
oct(x)
获取一个字符串的八进制
>>> oct(13) &#39;0o15&#39;
open(file, mode=&#39;r&#39;, buffering=-1, encoding=None, errors=None, newline=None, closefd=True, opener=None)
文件操作的函数,用来做文件操作的
# 打开一个文件 - >>> f = open("a.txt","r")
ord(c)
把一个字母转换为ASCII对对应表中的数字
>>> ord("a") 97 >>> ord("t") 116
pow(x, y[, z])
返回一个数的N次方
>>> pow(2, 10) 1024 >>> pow(2, 20) 1048576
print(*objects, sep=&#39; &#39;, end=&#39;n&#39;, file=sys.stdout, flush=False)
打印输出
>>> print("hello word") hello word
property(fget=None, fset=None, fdel=None, doc=None)
range(start, stop[, step])
生成一个序列
>>> range(10) range(0, 10) >>> for n in range(5): ... print(n) ... 0 1 2 3 4
repr(object)
返回一个包含对象的可打印表示的字符串
>>> repr(111) &#39;111&#39; >>> repr(111.11) &#39;111.11&#39;
reversed(seq)
对一个对象的元素进行反转
>>> li = [1, 2, 3, 4] >>> reversed(li)>>> for n in reversed(li): ... print(n) ... 4 3 2 1
round(number[, ndigits])
四舍五入
>>> round(3.3) 3 >>> round(3.7) 4
set([iterable])
创建一个数据类型为集合
>>> varss = set([11,222,333]) >>> type(varss)
setattr(object, name, value)
为某个对象设置一个属性
slice(start, stop[, step])
元素的切片操作都是调用的这个方法
sorted(iterable, key)
为一个对象的元素进行排序
代码:
#!/usr/bin/env python # _*_ coding:utf-8 _*_ char=[&#39;赵&#39;,"123", "1", "25", "65","679999999999", "a","B","alex","c" ,"A", "_", "ᒲ",&#39;a钱&#39;,&#39;孙&#39;,&#39;李&#39;,"余", &#39;佘&#39;,"佗", "㽙", "铱", "钲钲㽙㽙㽙"] new_chat = sorted(char) print(new_chat) for i in new_chat: print(bytes(i, encoding=&#39;utf-8&#39;))
输出结果:
C:\Python35\python.exe F:/Python_code/Note/soretd.py [&#39;1&#39;, &#39;123&#39;, &#39;25&#39;, &#39;65&#39;, &#39;679999999999&#39;, &#39;A&#39;, &#39;B&#39;, &#39;_&#39;, &#39;a&#39;, &#39;alex&#39;, &#39;a钱&#39;, &#39;c&#39;, &#39;ᒲ&#39;, &#39;㽙&#39;, &#39;佗&#39;, &#39;佘&#39;, &#39;余&#39;, &#39;孙&#39;, &#39;李&#39;, &#39;赵&#39;, &#39;钲钲㽙㽙㽙&#39;, &#39;铱&#39;] b&#39;1&#39; b&#39;123&#39; b&#39;25&#39; b&#39;65&#39; b&#39;679999999999&#39; b&#39;A&#39; b&#39;B&#39; b&#39;_&#39; b&#39;a&#39; b&#39;alex&#39; b&#39;a\xe9\x92\xb1&#39; b&#39;c&#39; b&#39;\xe1\x92\xb2&#39; b&#39;\xe3\xbd\x99&#39; b&#39;\xe4\xbd\x97&#39; b&#39;\xe4\xbd\x98&#39; b&#39;\xe4\xbd\x99&#39; b&#39;\xe5\xad\x99&#39; b&#39;\xe6\x9d\x8e&#39; b&#39;\xe8\xb5\xb5&#39; b&#39;\xe9\x92\xb2\xe9\x92\xb2\xe3\xbd\x99\xe3\xbd\x99\xe3\xbd\x99&#39; b&#39;\xe9\x93\xb1&#39; Process finished with exit code 0
staticmethod(function)
返回函数的静态方法
str(object=b&#39;&#39;, encoding=&#39;utf-8&#39;, errors=&#39;strict&#39;)
字符串
>>> a = str(111) >>> type(a)
sum(iterable[, start])
求和
>>> sum([11,22,33]) 66
super([type[, object-or-type]])
执行父类的构造方法
tuple([iterable])
创建一个对象,数据类型为元组
>>> tup = tuple([11,22,33,44]) >>> type(tup)
type(object)
查看一个对象的数据类型
>>> a = 1 >>> type(a)>>> a = "str" >>> type(a)
vars([object])
查看一个对象里面有多少个变量
zip(*iterables)
将两个元素相同的序列转换为字典
>>> li1 = ["k1","k2","k3"] >>> li2 = ["a","b","c"] >>> d = dict(zip(li1,li2)) >>> d {&#39;k1&#39;: &#39;a&#39;, &#39;k2&#39;: &#39;b&#39;, &#39;k3&#39;: &#39;c&#39;}
__import__(name, globals=None, locals=None, fromlist=(), level=0)
导入模块,把导入的模块作为一个别名
生成一个六位的随机验证码,且包含数字,数字的位置随机
# 导入random模块 import random temp = "" for i in range(6): num = random.randrange(0,4) if num == 3 or num == 1: rad2 = random.randrange(0,10) temp = temp + str(rad2) else: rad1 = random.randrange(65,91) c1 = chr(rad1) temp = temp + c1 print(temp)
输出结果
C:\Python35\python.exe F:/Python_code/sublime/Day06/built_in.py 72TD11