摘要：官方介紹內(nèi)置函數(shù)詳解返回?cái)?shù)字的絕對(duì)值，參數(shù)可以是整數(shù)或浮點(diǎn)數(shù)，如果參數(shù)是復(fù)數(shù)，則返回其大小。返回對(duì)象的命名屬性的值，必須是字符串，如果字符串是對(duì)象屬性之一的名稱(chēng)，則結(jié)果是該屬性的值。

The Python interpreter has a number of functions and types built into it that are always available. They are listed here in alphabetical order.

官方介紹：https://docs.python.org/3/lib...

abs(x)

返回?cái)?shù)字的絕對(duì)值，參數(shù)可以是整數(shù)或浮點(diǎn)數(shù)，如果參數(shù)是復(fù)數(shù)，則返回其大小。

# 如果參數(shù)是復(fù)數(shù)，則返回其大小。
 >>> abs(-25)
25
 >>> abs(25)
25

all(iterable)

all()會(huì)循環(huán)括號(hào)內(nèi)的每一個(gè)元素，如果括號(hào)內(nèi)的所有元素都是真的，或者如果iterable為空，則返回True，如果有一個(gè)為假的那么就返回False

>>> all([])
True
>>> all([1,2,3])
True
>>> all([1,2,""])
False
# 如果有一個(gè)為假，則都為假
>>> all([1,2,None])
False

假的參數(shù)有：False、0、None、""、[]、()、{}等，查看一個(gè)元素是否為假可以使用bool進(jìn)行查看。

any(iterable)

循環(huán)元素，如果有一個(gè)元素為真，那么就返回True，否則就返回False

 >>> any([0,1])
True
 >>> any([0])
False

ascii(object)

在對(duì)象的類(lèi)中尋找__repr__方法，獲取返回值

 >>> class Foo:
 ...  def __repr_(self):
 ...     return "hello"
 ...
 >>> obj = Foo()
 >>> r = ascii(obj)
 >>> print(r)
# 返回的是一個(gè)可迭代的對(duì)象
<__main__.Foo object at 0x000001FDEE13D320>

bin(x)

將整數(shù)x轉(zhuǎn)換為二進(jìn)制字符串，如果x不為Python中int類(lèi)型，x必須包含方法__index__()并且返回值為integer

# 返回一個(gè)整數(shù)的二進(jìn)制
 >>> bin(999)
"0b1111100111"

# 非整型的情況，必須包含__index__()方法切返回值為integer的類(lèi)型
 >>> class myType:
 ...   def __index__(self):
 ...       return 35
 ...
 >>> myvar = myType()
 >>> bin(myvar)
"0b100011"

bool([x])

查看一個(gè)元素的布爾值，非真即假

 >>> bool(0)
False
 >>> bool(1)
True
 >>> bool([1])
True
 >>> bool([10])
True

bytearray([source [, encoding [, errors]]])

返回一個(gè)byte數(shù)組，Bytearray類(lèi)型是一個(gè)可變的序列，并且序列中的元素的取值范圍為 [0 ,255]。

source參數(shù)：

如果source為整數(shù)，則返回一個(gè)長(zhǎng)度為source的初始化數(shù)組；

如果source為字符串，則按照指定的encoding將字符串轉(zhuǎn)換為字節(jié)序列；

如果source為可迭代類(lèi)型，則元素必須為[0 ,255]中的整數(shù)；

如果source為與buffer接口一致的對(duì)象，則此對(duì)象也可以被用于初始化bytearray.。

 >>> bytearray(3)
bytearray(b"x00x00x00")

bytes([source[, encoding[, errors]]])

 >>> bytes("asdasd",encoding="utf-8")
b"asdasd"

callable(object)

返回一個(gè)對(duì)象是否可以被執(zhí)行

 >>> def func():
 ...  return 123
 ...
 >>> callable(func)
True
 >>> func = 123
 >>> callable(func)
False

chr(i)

返回一個(gè)數(shù)字在ASCII編碼中對(duì)應(yīng)的字符，取值范圍256個(gè)

 >>> chr(66)
"B"
 >>> chr(5)
"x05"
 >>> chr(55)
"7"
 >>> chr(255)
"xff"
 >>> chr(25)
"x19"
 >>> chr(65)
"A"

classmethod(function)

返回函數(shù)的類(lèi)方法

compile(source, filename, mode, flags=0, dont_inherit=False, optimize=-1)

把字符串編譯成python可執(zhí)行的代碼

 >>> str = "for i in range(0,10): print(i)"
 >>> c = compile(str,"","exec")
 >>> exec(c)
0
1
2
3
4
5
6
7
8
9

complex([real[, imag]])

創(chuàng)建一個(gè)值為real + imag * j的復(fù)數(shù)或者轉(zhuǎn)化一個(gè)字符串或數(shù)為復(fù)數(shù)。如果第一個(gè)參數(shù)為字符串，則不需要指定第二個(gè)參數(shù)

 >>> complex(1, 2)
(1+2j)
# 數(shù)字
 >>> complex(1)
(1+0j)
# 當(dāng)做字符串處理
 >>> complex("1")
(1+0j)
# 注意：這個(gè)地方在“+”號(hào)兩邊不能有空格，也就是不能寫(xiě)成"1 + 2j"，應(yīng)該是"1+2j"，否則會(huì)報(bào)錯(cuò)
 >>> complex("1+2j")
(1+2j)

delattr(object, name)

刪除對(duì)象的屬性值

>>> class cls:
...   @classmethod
...   def echo(self):
...     print("CLS")
... 
>>> cls.echo()
CLS
>>> delattr(cls, "echo")
>>> cls.echo()
Traceback (most recent call last):
  File "", line 1, in 
AttributeError: type object "cls" has no attribute "echo"

dict(**kwarg)

創(chuàng)建一個(gè)數(shù)據(jù)類(lèi)型為字典

 >>> dic = dict({"k1":"123","k2":"456"})
 >>> dic
{"k1": "123", "k2": "456"}

dir([object])

返回一個(gè)對(duì)象中中的所有方法

 >>> dir(str)
["__add__", "__class__", "__contains__", "__delattr__", "__dir__", "__doc__", "__eq__", "__format__", "__ge__", "__getattribute__", "__getitem__", "__getnewargs__", "__gt__", "__hash__", "__init__", "__iter__", "__le__", "__len__", "__lt__", "__mod__", "__mul__", "__ne__", "__new__", "__reduce__", "__reduce\_ex__", "__repr__", "__rmod__", "__rmul__", "__setattr__", "__sizeof__", "__str__", "__subclasshook__", "capitalize", "casefold", "center", "count", "encode", "endswith", "expandtabs", "find", "format", "format_map", "index", "isalnum", "isalpha", "isdecimal", "isdigit", "isidentifier", "islower", "isnumeric", "isprintable", "isspace", "istitle", "isupper", "join", "ljust", "lower", "lstrip", "maketrans", "partition", "replace", "rfind", "rindex", "rjust", "rpartition", "rsplit", "rstrip", "split", "splitlines", "startswith", "strip", "swapcase", "title", "translate", "upper", "zfill"]

divmod(a, b)

返回的是a//b（除法取整）以及a對(duì)b的余數(shù)，返回結(jié)果類(lèi)型為tuple

 >>> divmod(10, 3)
(3, 1)

enumerate(iterable, start=0)

為元素生成下標(biāo)

 >>> 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)

把一個(gè)字符串當(dāng)作一個(gè)表達(dá)式去執(zhí)行

 >>> string = "1 + 3"
 >>> string
"1 + 3"
 >>> eval(string)
4

exec(object[, globals[, locals]])

把字符串當(dāng)作python代碼執(zhí)行

 >>> exec("for n in range(5): print(n)")
0
1
2
3
4

filter(function, iterable)

篩選過(guò)濾，循環(huán)可迭代的對(duì)象，把迭代的對(duì)象當(dāng)作函數(shù)的參數(shù)，如果符合條件就返回True，否則就返回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])

將整數(shù)和字符串轉(zhuǎn)換成浮點(diǎn)數(shù)

 >>> float("124")
124.0
 >>> float("123.45")
123.45
 >>> float("-123.34")
-123.34

format(value[, format_spec])

字符串格式化

詳鍵：https://blog.ansheng.me/artic...

frozenset([iterable])

frozenset是凍結(jié)的集合，它是不可變的，存在哈希值，好處是它可以作為字典的key，也可以作為其它集合的元素。缺點(diǎn)是一旦創(chuàng)建便不能更改，沒(méi)有add，remove方法。

getattr(object, name[, default])

返回對(duì)象的命名屬性的值，name必須是字符串，如果字符串是對(duì)象屬性之一的名稱(chēng)，則結(jié)果是該屬性的值。

globals()

獲取或修改當(dāng)前文件內(nèi)的全局變量

>>> a = "12"
>>> bsd = "54asd"
>>> globals()
{"__doc__": None, "a": "12", "__loader__": , "bsd": "54asd", "__builtins__": , "n": "__doc__", "__name__": "__main__", "__spec__": None, "__package__": None}

hasattr(object, name)

參數(shù)是一個(gè)對(duì)象和一個(gè)字符串，如果字符串是對(duì)象的某個(gè)屬性的名稱(chēng)，則結(jié)果為T(mén)rue，否則為False。

hash(object)

返回一個(gè)對(duì)象的hash值

 >>> a = "asdadasdwqeq234sdfdf"
 >>> hash(a)
5390438057823015497

help([object])

查看一個(gè)類(lèi)的所有詳細(xì)方法，或者查看某個(gè)方法的使用詳細(xì)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"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)

獲取一個(gè)數(shù)的十六進(jìn)制

 >>> hex(13)
"0xd"

id(object)

返回一個(gè)對(duì)象的內(nèi)存地址

 >>> a = 123
 >>> id(a)
1835400816

input([prompt])

交互式輸入

 >>> name = input("Pless your name: ")
Pless your name: ansheng
 >>> print(name)
ansheng

int(x, base=10)

獲取一個(gè)數(shù)的十進(jìn)制

 >>> int("31")
31

也可以作為進(jìn)制轉(zhuǎn)換

 >>> int(10)
10
 >>> int("0b11",base=2)
3
 >>> int("11",base=8)
9
 >>> int("0xe",base=16)
14

isinstance(object, classinfo)

判斷對(duì)象是否是這個(gè)類(lèi)創(chuàng)建的

>>> li = [11,22,33]
>>> isinstance(li,list)
True

issubclass(class, classinfo)

查看一個(gè)對(duì)象是否為子類(lèi)

iter(object[, sentinel])

創(chuàng)建一個(gè)可迭代的對(duì)象

 >>> obj = iter([11,22,33,44])
 >>> obj

 >>> for n in obj:
 ...  print(n)
 ...
11
22
33
44

len(s)

查看一個(gè)對(duì)象的長(zhǎng)度

 >>> url="ansheng.me"
 >>> len(url)
10

list([iterable])

創(chuàng)建一個(gè)數(shù)據(jù)類(lèi)型為列表

 >>> li = list([11,22,33,44])
 >>> li
[11, 22, 33, 44]

locals()

返回當(dāng)前作用域的局部變量，以字典形式輸出

 >>> func()
 >>> def func():
 ...  name="ansheng"
 ...  print(locals())
 ...
 >>> func()
{"name": "ansheng"}

map(function, iterable, ...)

對(duì)一個(gè)序列中的每一個(gè)元素都傳到函數(shù)中執(zhí)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])

取一個(gè)對(duì)象中的最大值

 >>> li = list([11,22,33,44])
 >>> li = [11,22,33,44]
 >>> max(li)
44

memoryview(obj)

返回對(duì)象obj的內(nèi)存查看對(duì)象

 >>> import struct
 >>> buf = struct.pack("i"*12, *list(range(12)))
 >>> x = memoryview(buf)
 >>> y = x.cast("i", 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])

取一個(gè)對(duì)象中的最小值

 >>> li = list([11,22,33,44])
 >>> li = [11,22,33,44]
 >>> min(li)
11

next(iterator[, default])

每次只拿取可迭代對(duì)象的一個(gè)元素

 >>> obj = iter([11,22,33,44])
 >>> next(obj)
11
 >>> next(obj)
22
 >>> next(obj)
33
 >>> next(obj)
44
 >>> next(obj)
 # 如果沒(méi)有可迭代的元素了就會(huì)報(bào)錯(cuò)
Traceback (most recent call last):
  File "", line 1, in 
StopIteration

object

返回一個(gè)新的無(wú)特征對(duì)象

oct(x)

獲取一個(gè)字符串的八進(jìn)制

 >>> oct(13)
"0o15"

open(file, mode="r", buffering=-1, encoding=None, errors=None, newline=None, closefd=True, opener=None)

文件操作的函數(shù)，用來(lái)做文件操作的

 # 打開(kāi)一個(gè)文件
- >>> f = open("a.txt","r")

ord(c)

把一個(gè)字母轉(zhuǎn)換為ASCII對(duì)對(duì)應(yīng)表中的數(shù)字

 >>> ord("a")
97
 >>> ord("t")
116

pow(x, y[, z])

返回一個(gè)數(shù)的N次方

 >>> pow(2, 10)
1024
 >>> pow(2, 20)
1048576

print(*objects, sep=" ", end="n", file=sys.stdout, flush=False)

打印輸出

 >>> print("hello word")
hello word

property(fget=None, fset=None, fdel=None, doc=None)

range(start, stop[, step])

生成一個(gè)序列

 >>> range(10)
range(0, 10)
 >>> for n in range(5):
 ...  print(n)
 ...
0
1
2
3
4

repr(object)

返回一個(gè)包含對(duì)象的可打印表示的字符串

>>> repr(111)
"111"
>>> repr(111.11)
"111.11"

reversed(seq)

對(duì)一個(gè)對(duì)象的元素進(jìn)行反轉(zhuǎn)

 >>> 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])

創(chuàng)建一個(gè)數(shù)據(jù)類(lèi)型為集合

 >>> varss = set([11,222,333])
 >>> type(varss)

setattr(object, name, value)

為某個(gè)對(duì)象設(shè)置一個(gè)屬性

slice(start, stop[, step])

元素的切片操作都是調(diào)用的這個(gè)方法

sorted(iterable, key)

為一個(gè)對(duì)象的元素進(jìn)行排序

代碼：

#!/usr/bin/env python
# _*_ coding:utf-8 _*_

char=["趙","123", "1", "25", "65","679999999999", "a","B","alex","c" ,"A", "_", "?","a錢(qián)","孫","李","余", "佘","佗", "?", "銥", "鉦鉦???"]

new_chat = sorted(char)
print(new_chat)
for i in new_chat:
    print(bytes(i, encoding="utf-8"))

輸出結(jié)果：

C:Python35python.exe F:/Python_code/Note/soretd.py
["1", "123", "25", "65", "679999999999", "A", "B", "_", "a", "alex", "a錢(qián)", "c", "?", "?", "佗", "佘", "余", "孫", "李", "趙", "鉦鉦???", "銥"]
b"1"
b"123"
b"25"
b"65"
b"679999999999"
b"A"
b"B"
b"_"
b"a"
b"alex"
b"axe9x92xb1"
b"c"
b"xe1x92xb2"
b"xe3xbdx99"
b"xe4xbdx97"
b"xe4xbdx98"
b"xe4xbdx99"
b"xe5xadx99"
b"xe6x9dx8e"
b"xe8xb5xb5"
b"xe9x92xb2xe9x92xb2xe3xbdx99xe3xbdx99xe3xbdx99"
b"xe9x93xb1"

Process finished with exit code 0

staticmethod(function)

返回函數(shù)的靜態(tài)方法

str(object=b"", encoding="utf-8", errors="strict")

字符串

 >>> a = str(111)
 >>> type(a)

sum(iterable[, start])

求和

 >>> sum([11,22,33])
66

super([type[, object-or-type]])

執(zhí)行父類(lèi)的構(gòu)造方法

tuple([iterable])

創(chuàng)建一個(gè)對(duì)象，數(shù)據(jù)類(lèi)型為元組

>>> tup = tuple([11,22,33,44])
>>> type(tup)

type(object)

查看一個(gè)對(duì)象的數(shù)據(jù)類(lèi)型

 >>> a = 1
 >>> type(a)

 >>> a = "str"
 >>> type(a)

vars([object])

查看一個(gè)對(duì)象里面有多少個(gè)變量

zip(*iterables)

將兩個(gè)元素相同的序列轉(zhuǎn)換為字典

>>> li1 = ["k1","k2","k3"]
>>> li2 = ["a","b","c"]
>>> d = dict(zip(li1,li2))
>>> d
{"k1": "a", "k2": "b", "k3": "c"}

__import__(name, globals=None, locals=None, fromlist=(), level=0)

導(dǎo)入模塊，把導(dǎo)入的模塊作為一個(gè)別名

生成一個(gè)六位的隨機(jī)驗(yàn)證碼，且包含數(shù)字，數(shù)字的位置隨機(jī)

# 導(dǎo)入random模塊
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)

輸出結(jié)果

C:Python35python.exe F:/Python_code/sublime/Day06/built_in.py
72TD11

原文鏈接