python學習日誌20 3 12

2021-10-03 19:55:59 字數 4741 閱讀 7526

>>


>


import keyword


>>


>


print


(keyword.kwlist)


['false'


,'none'


,'true'


,'and'


,'as'


,'assert'


,'async'


,'await'


,'break'


,'class'


,'continue'


,'def'


,'del'


,'elif'


,'else'


,'except'


,'finally'


,'for'


,'from'


,'global'


,'if'


,'import'


,'in'


,'is'


,'lambda'


,'nonlocal'


,'not'


,'or'


,'pass'


,'raise'


,'return'


,'try'


,'while'


,'with'


,'yield'


]
2、系統內建的模組名、型別名或函式名以及已導 入的模組名及其成員名作變數名

>>


>


dir(__builtins__)


['arithmeticerror'


,'assertionerror'


,'attributeerror'


,'baseexception'


,'blockingioerror'


,'brokenpipeerror'


,'buffererror'


,'byteswarning'


,'childprocesserror'


,'connectionabortederror'


,'connectionerror'


,'connectionrefusederror'


,'connectionreseterror'


,'deprecationwarning'


,'eoferror'


,'ellipsis'


,'environmenterror'


,'exception'


,'false'


,'fileexistserror'


,'filenotfounderror'


,'floatingpointerror'


,'futurewarning'


,'generatorexit'


,'ioerror'


,'importerror'


,'importwarning'


,'indentationerror'


,'indexerror'


,'interruptederror'


,'isadirectoryerror'


,'keyerror'


,'keyboardinterrupt'


,'lookuperror'


,'memoryerror'


,'modulenotfounderror'


,'nameerror'


,'none'


,'notadirectoryerror'


,'notimplemented'


,'notimplementederror'


,'oserror'


,'overflowerror'


,'pendingdeprecationwarning'


,'permissionerror'


,'processlookuperror'


,'recursionerror'


,'referenceerror'


,'resourcewarning'


,'runtimeerror'


,'runtimewarning'


,'stopasynciteration'


,'stopiteration'


,'syntaxerror'


,'syntaxwarning'


,'systemerror'


,'systemexit'


,'taberror'


,'timeouterror'


,'true'


,'typeerror'


,'unboundlocalerror'


,'unicodedecodeerror'


,'unicodeencodeerror'


,'unicodeerror'


,'unicodetranslateerror'


,'unicodewarning'


,'userwarning'


,'valueerror'


,'warning'


,'windowserror'


,'zerodivisionerror'


,'__build_class__'


,'__debug__'


,'__doc__'


,'__import__'


,'__loader__'


,'__name__'


,'__package__'


,'__spec__'


,'abs'


,'all'


,'any'


,'ascii'


,'bin'


,'bool'


,'breakpoint'


,'bytearray'


,'bytes'


,'callable'


,'chr'


,'classmethod'


,'compile'


,'complex',,


'credits'


,'delattr'


,'dict'


,'dir'


,'divmod'


,'enumerate'


,'eval'


,'exec'


,'exit'


,'filter'


,'float'


,'format'


,'frozenset'


,'getattr'


,'globals'


,'hasattr'


,'hash'


,'help'


,'hex'


,'id'


,'input'


,'int'


,'isinstance'


,'issubclass'


,'iter'


,'len'


,'license'


,'list'


,'locals'


,'map'


,'max'


,'memoryview'


,'min'


,'next'


,'object'


,'oct'


,'open'


,'ord'


,'pow'


,'print'


,'property'


,'quit'


,'range'


,'repr'


,'reversed'


,'round'


,'set'


,'setattr'


,'slice'


,'sorted'


,'staticmethod'


,'str'


,'sum'


,'super'


,'tuple'


,'type'


,'vars'


,'zip'


]
3、複數

>>


> c =5+


6j>>


> c.real


5.0>>


> c.imag


6.0
>>


> c.conjugate(


)#返回共軛複數(5


-6j)
4、字串格式化（不明白什麼意思）

>>


> a =


3.1485


>>


>


"%7.3f"


% a#向右對齊，保留三位小數


' 3.148'


>>


>


"%d is %c"%(


65,65)


'65 is a'


>>


>


"many name is %s and my age is %d"%(


'wei',20


)'many name is wei and my age is 20'
5、逗號在python中僅起到分隔作用

>>


>


'a'in


'b',


'a'(


false


,'a'


)>>


>


'a'in


('b'


,'a'


)true


>>


> x =3,


5>>


> x(3


,5)>>


>3==


3,5(


true,5


)

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