1.abs取绝对值

>>> abs(9.8)9.8>>> abs(-9.8)9.82.dic()变为字典类型

>>> dict({"key":"value"}){'key': 'value'}3.help()显示帮助信息

>>> help(map)Help on class map in module builtins:class map(object) | map(func, *iterables) --> map object | | Make an iterator that computes the function using arguments from-- More --4.min取数据中的最小值,max取数据中的最大值

print(min([3, 4, 2]))print(min("wqeqwe"))print(min((3, 6, 4)))print(max([3, 4, 2]))print(max("wqeqwe"))print(max((3, 6, 4)))E:\PythonProject\python-test\venvP3\Scripts\python.exe E:/PythonProject/python-test/BasicGrammer/test.py2e34w6Process finished with exit code 05.all()所有的为true,才返回true。空的列表返回true

print(all([1, 2, 0])) # 列表中的0是False,所以返回Falseprint(all([1, 2, 5])) # 列表中的所有值都是True,所以返回Trueprint(all([])) # 空的列表,all()返回trueprint(help(all))E:\PythonProject\python-test\venvP3\Scripts\python.exe E:/PythonProject/python-test/BasicGrammer/test.pyFalseTrueTrueHelp on built-in function all in module builtins:all(iterable, /) Return True if bool(x) is True for all values x in the iterable. If the iterable is empty, return True.NoneProcess finished with exit code 06.any()任意一个为true就返回true。空的列表返回false

any()列表中的任意一个为True,就返回Trueprint(any([1, 2, 0])) print(any([1, 2, 5])) # 列表中的任意一个是True,就返回Trueprint(any([])) # 空的列表,any()返回falseprint(help(any))E:\PythonProject\python-test\venvP3\Scripts\python.exe E:/PythonProject/python-test/BasicGrammer/test.pyTrueTrueFalseHelp on built-in function any in module builtins:any(iterable, /) Return True if bool(x) is True for any x in the iterable. If the iterable is empty, return False.NoneProcess finished with exit code 07.dir()打印当前程序的所有变量

print(dir()) # 打印当前程序的所有变量E:\PythonProject\python-test\venvP3\Scripts\python.exe E:/PythonProject/python-test/BasicGrammer/test.py['__annotations__', '__builtins__', '__cached__', '__doc__', '__file__', '__loader__', '__name__', '__package__', '__spec__']Process finished with exit code 08.hex()把十进制数转换为16进制数

hex()转换为16进制print(hex(16)) E:\PythonProject\python-test\venvP3\Scripts\python.exe E:/PythonProject/python-test/BasicGrammer/test.py0x10Process finished with exit code 09.slice()切片

>>> l = [2,3,4,5,6,7]>>> s = slice(1,5,2)>>> l(s)Traceback (most recent call last): File "<stdin>", line 1, in <module>TypeError: 'list' object is not callable>>> l[s][3, 5]10.divmod()求商和余数

>>> divmod(10,3)(3, 1)>>> divmod(10,2)(5, 0)>>>11.sorted()排序

>>> sorted([1,9,4])[1, 4, 9]d = {1: 0, 10: 4, 9: 2, 15: 3}print(d.items())print(sorted(d.items(), key=lambda x: x[1], reverse=True))E:\PythonProject\python-test\venvP3\Scripts\python.exe E:/PythonProject/python-test/BasicGrammer/test.pydict_items([(1, 0), (10, 4), (9, 2), (15, 3)])[(10, 4), (15, 3), (9, 2), (1, 0)]Process finished with exit code 013.ascii()转换为ascii码

>>> ascii("qwqw我")"'qwqw\\u6211'"14.oct()十进制数转换为8进制数

>>> print(oct(8))0o1015.bin()十进制数转换为二进制数

>>> print(bin(10))0b101016.eval()把字符转换为里面原有的含义,把字符串转换为代码

print(eval("{1:2}"))E:\PythonProject\python-test\venvP3\Scripts\python.exe E:/PythonProject/python-test/BasicGrammer/test.py{1: 2}Process finished with exit code 0print(eval("1+2*3"))E:\PythonProject\python-test\venvP3\Scripts\python.exe E:/PythonProject/python-test/BasicGrammer/test.py7Process finished with exit code 0eval('print("hello")')E:\PythonProject\python-test\venvP3\Scripts\python.exe E:/PythonProject/python-test/BasicGrammer/test.pyhelloProcess finished with exit code 0eval()只能解析单行代码,不能解析多行的代码code = '''if 3 > 2: print("3>2")'''eval(code)E:\PythonProject\python-test\venvP3\Scripts\python.exe E:/PythonProject/python-test/BasicGrammer/test.pyTraceback (most recent call last): File "E:/PythonProject/python-test/BasicGrammer/test.py", line 9, in <module> eval(code) File "<string>", line 2 if 3 > 2: ^SyntaxError: invalid syntaxProcess finished with exit code 117.exec()可以解析执行多行代码,但是获取不到函数的返回值,eval()可以

code = '''if 3 > 2: print("3>2")'''exec(code)E:\PythonProject\python-test\venvP3\Scripts\python.exe E:/PythonProject/python-test/BasicGrammer/test.py3>2Process finished with exit code 0code = '''def foo(): if 3 > 2: print("3>2") return 3foo()'''re_exec = exec(code)print(re_exec)E:\PythonProject\python-test\venvP3\Scripts\python.exe E:/PythonProject/python-test/BasicGrammer/test.py3>2NoneProcess finished with exit code 0print(eval("1+2+3"))print(exec("1+2+3"))E:\PythonProject\python-test\venvP3\Scripts\python.exe E:/PythonProject/python-test/BasicGrammer/test.py6NoneProcess finished with exit code 018.ord()获取对应的ascii码表中的值。chr()获取ascii表中对应的字符

ord() 获取对应的ascii码表中的值chr() 获取ascii表中值对应的字符>>> ord("a")97>>> chr(97)'a'19.sum()求和

>>> sum((1,2,3))6>>> sum([1,2,3])6>>> sum({1:2,3:4})4>>> sum({1,2,3,4})10>>> sum("123")Traceback (most recent call last): File "<stdin>", line 1, in <module>TypeError: unsupported operand type(s) for +: 'int' and 'str'>>>20.bytearray()可通过encode,decode之后,通过index来修改字符串中的值

>>> s = "woai中国">>> s[0] = "W"Traceback (most recent call last): File "<stdin>", line 1, in <module>TypeError: 'str' object does not support item assignment>>> s = bytearray(s)Traceback (most recent call last): File "<stdin>", line 1, in <module>TypeError: string argument without an encoding>>> s = s.encode('utf-8')>>> sb'woai\xe4\xb8\xad\xe5\x9b\xbd'>>> s = bytearray(s)>>> sbytearray(b'woai\xe4\xb8\xad\xe5\x9b\xbd')>>> s[0]='W'Traceback (most recent call last): File "<stdin>", line 1, in <module>TypeError: an integer is required>>> s[0]=97>>> sbytearray(b'aoai\xe4\xb8\xad\xe5\x9b\xbd')>>> s.decode('utf-8')'aoai中国'21.id()查看变量的内存地址

>>> id(s[0]) # s[0]的内存地址会变1487327920>>> s[0]=66>>> id(s[0])1487326928>>> id(s)2879739806752 # s的内存地址是不变的>>> s[0]=67>>> id(s)287973980675222.map()通过匿名函数lambda来对列表中的数据进行操作

map()>>> list(map(lambda x:x*x,[1,2,3]))[1, 4, 9]filter()>>> list(filter(lambda x:x>3,[1,2,3,4,5]))[4, 5]23.reduce()对数据进行整合操作,返回一个值

>>> import functools>>> functools.reduce(lambda x,y:x+y,[1,2,3,4])10>>> functools.reduce(lambda x,y:x*y,[1,2,3,4])24>>> functools.reduce(lambda x,y:x*y,[1,2,3,4],2)48>>> functools.reduce(lambda x,y:x*y,[1,2,3,4],3)72>>> functools.reduce(lambda x,y:x+y,[1,2,3,4],3)1324.print()

def print(self, *args, sep=' ', end='\n', file=None): # known special case of print """ print(value, ..., sep=' ', end='\n', file=sys.stdout, flush=False) Prints the values to a stream, or to sys.stdout by default. Optional keyword arguments: file: a file-like object (stream); defaults to the current sys.stdout. sep: string inserted between values, default a space. end: string appended after the last value, default a newline. flush: whether to forcibly flush the stream. """ pass#!/usr/bin/env python# -*- coding:utf-8 -*-# Author: vitamsg = "msg"# 文件的模式必须是可写入模式(w,r+),不能是只读模式f = open(file="写文件.txt", mode="w", encoding="utf-8")print(msg, "my input", sep="|", end=":::",file=f)运行程序E:\PythonProject\python-test\venvP3\Scripts\python.exe E:/PythonProject/python-test/BasicGrammer/test.pyProcess finished with exit code 0查看"写文件.txt"msg|my input:::25.tupple()把可迭代的数据类型变为元组

>>> a = [1,2,3]>>> tuple(a)(1, 2, 3)>>> tuple("1,2,3")('1', ',', '2', ',', '3')>>> tuple({1:2})(1,)>>> tuple(2)Traceback (most recent call last): File "<stdin>", line 1, in <module>TypeError: 'int' object is not iterable26.callable()判断是否可调用,即通过abs()方式调用,函数是可调用的,可用于判断是否是函数

callable()判断是否可调用,即通过abc()方式调用函数是可调用的,可用于判断是否是函数>>> callable(abs)True>>> callable(list)True>>> callable([1,2,3])False27.frozenset()变为不可变集合

>>> s = frozenset({1,2,3})>>> s.discard(2)Traceback (most recent call last): File "<stdin>", line 1, in <module>AttributeError: 'frozenset' object has no attribute 'discard'28.vars()包含变量的名和变量的值,dir()只是变量的名字

>>> vars(){'__name__': '__main__', '__doc__': None, '__package__': None, '__loader__': <class '_frozen_importlib.BuiltinImporter'>, '__spec__': None, '__annotations__': {}, '__builtins__': <module 'builtins'(built-in)>, 'l': [2, 3, 4, 5, 6, 7], 's': bytearray(b'aoaini'), 'd': {10: 2, 12: 1, 9: 0}, 'a': [1, 2, 3]}['__annotations__', '__builtins__', '__doc__', '__loader__', '__name__', '__package__', '__spec__', 'a', 'd', 'l', 's']>>>29.locals()打印局部变量,globals()打印全局变量

>>> globals(){'__name__': '__main__', '__doc__': None, '__package__': None, '__loader__': <class '_frozen_importlib.BuiltinImporter'>, '__spec__': None, '__annotations__': {}, '__builtins__': <module 'builtins' (built-in)>, 'l': [2, 3, 4, 5, 6, 7], 's': bytearray(b'aoaini'), 'd': {10: 2, 12: 1, 9: 0}, 'a': [1, 2, 3]}>>> locals(){'__name__': '__main__', '__doc__': None, '__package__': None, '__loader__': <class '_frozen_importlib.BuiltinImporter'>, '__spec__': None, '__annotations__': {}, '__builtins__': <module 'builtins' (built-in)>, 'l': [2, 3, 4, 5, 6, 7], 's': bytearray(b'aoaini'), 'd': {10: 2, 12: 1, 9: 0}, 'a': [1, 2, 3]}>>>30.repr显示形式变为字符串

>>> repr(abs(23))'23'>>> repr(frozenset({12,4}))'frozenset({12, 4})'>>> repr({1,2,3})'{1, 2, 3}'>>>31.zip

>>> a = [1,2,3,4,5]>>> b = ["a","b","c"]>>> zip(a)<zip object at 0x00000237FF9EAF08>>>> zip(a,b)<zip object at 0x00000237FF9D8448>>>> list(zip(a,b))[(1, 'a'), (2, 'b'), (3, 'c')]>>> dict(zip(a,b)){1: 'a', 2: 'b', 3: 'c'}>>> str(zip(a,b))'<zip object at 0x00000237FF9EAF08>'>>> tuple(zip(a,b))((1, 'a'), (2, 'b'), (3, 'c'))>>>32.complex()变为复数

>>> complex(3,5)(3+5j)>>> complex(3)(3+0j)33.round()保留几位小数位

>>> round(3.12123333333334444445555555555555555,18)3.1212333333333446>>> round(3.12123333333334444445555555555555555,2)3.1234.hash()把字符串变为固定长度的hash值

不可变数据类型才是可hash的,包含整数,字符串,元组,都是不可变的,是可hash的>>> hash("12")8731980002792086209>>> hash("123")-1620719444414375290>>> hash([1,2])Traceback (most recent call last): File "<stdin>", line 1, in <module>TypeError: unhashable type: 'list'>>> hash(1)1>>> hash(123)123>>> hash((1,2))3713081631934410656>>> hash((1,2,3))2528502973977326415>>> hash({1,2,3})Traceback (most recent call last): File "<stdin>", line 1, in <module>TypeError: unhashable type: 'set'>>>35.set()把可迭代对象变为集合集合

>>> set([1,2,3]){1, 2, 3}>>> set((1,2,3)){1, 2, 3}>>> set("21"){'1', '2'}>>> set(2)Traceback (most recent call last): File "<stdin>", line 1, in <module>TypeError: 'int' object is not iterable>>> set({1:2,3:4}){1, 3}>>>