Python built-in function - set&frozenset
##set
set() set对象实例化 >>> set('add') set(['a', 'd']) >>> set('python').add('hello') >>> print set('python').add('hello') None >>> a = set('python') >>> a set(['h', 'o', 'n', 'p', 't', 'y']) >>> a.add('hello') >>> a set(['h', 'o', 'n', 'p', 't', 'y', 'hello']) >>> a.update('python') >>> a set(['h', 'o', 'n', 'p', 't', 'y', 'hello']) >>> a.update('hello') >>> a set(['e', 'h', 'l', 'o', 'n', 'p', 't', 'y', 'hello']) >>> a.remove('hello') >>> a set(['e', 'h', 'l', 'o', 'n', 'p', 't', 'y']) >>> b = set('hello') >>> b set(['h', 'e', 'l', 'o']) >>> a - b set(['y', 'p', 't', 'n']) >>> a & b set(['h', 'e', 'l', 'o']) >>> a | b set(['e', 'h', 'l', 'o', 'n', 'p', 't', 'y']) >>> a != b True >>> a == b False >>> b in a False >>> a in b False >>> c = set('hell') >>> c in b False >>> b set(['h', 'e', 'l', 'o']) >>> c set(['h', 'e', 'l']) >>> 'h' in c True >>> 'p' in c Falsefrozenset
frozenset([iterable]) 产生一个不可变的set >>> a = frozenset(range(10)) >>> a frozenset([0, 1, 2, 3, 4, 5, 6, 7, 8, 9]) >>> a.remove(0) Traceback (most recent call last): File "<pyshell#189>", line 1, in <module> a.remove(0) AttributeError: 'frozenset' object has no attribute 'remove' >>> b = set(range(10)) >>> b set([0, 1, 2, 3, 4, 5, 6, 7, 8, 9]) >>> b.remove(1) >>> b set([0, 2, 3, 4, 5, 6, 7, 8, 9])The above is the content of Python’s built-in function-set&frozenset. For more related content, please pay attention to the PHP Chinese website (www.php.cn)!

Pythonlistscanstoreanydatatype,arraymodulearraysstoreonetype,andNumPyarraysarefornumericalcomputations.1)Listsareversatilebutlessmemory-efficient.2)Arraymodulearraysarememory-efficientforhomogeneousdata.3)NumPyarraysareoptimizedforperformanceinscient

WhenyouattempttostoreavalueofthewrongdatatypeinaPythonarray,you'llencounteraTypeError.Thisisduetothearraymodule'sstricttypeenforcement,whichrequiresallelementstobeofthesametypeasspecifiedbythetypecode.Forperformancereasons,arraysaremoreefficientthanl

Pythonlistsarepartofthestandardlibrary,whilearraysarenot.Listsarebuilt-in,versatile,andusedforstoringcollections,whereasarraysareprovidedbythearraymoduleandlesscommonlyusedduetolimitedfunctionality.

ThescriptisrunningwiththewrongPythonversionduetoincorrectdefaultinterpretersettings.Tofixthis:1)CheckthedefaultPythonversionusingpython--versionorpython3--version.2)Usevirtualenvironmentsbycreatingonewithpython3.9-mvenvmyenv,activatingit,andverifying

Pythonarrayssupportvariousoperations:1)Slicingextractssubsets,2)Appending/Extendingaddselements,3)Insertingplaceselementsatspecificpositions,4)Removingdeleteselements,5)Sorting/Reversingchangesorder,and6)Listcomprehensionscreatenewlistsbasedonexistin

NumPyarraysareessentialforapplicationsrequiringefficientnumericalcomputationsanddatamanipulation.Theyarecrucialindatascience,machinelearning,physics,engineering,andfinanceduetotheirabilitytohandlelarge-scaledataefficiently.Forexample,infinancialanaly

Useanarray.arrayoveralistinPythonwhendealingwithhomogeneousdata,performance-criticalcode,orinterfacingwithCcode.1)HomogeneousData:Arrayssavememorywithtypedelements.2)Performance-CriticalCode:Arraysofferbetterperformancefornumericaloperations.3)Interf

No,notalllistoperationsaresupportedbyarrays,andviceversa.1)Arraysdonotsupportdynamicoperationslikeappendorinsertwithoutresizing,whichimpactsperformance.2)Listsdonotguaranteeconstanttimecomplexityfordirectaccesslikearraysdo.


Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Hot Tools

mPDF
mPDF is a PHP library that can generate PDF files from UTF-8 encoded HTML. The original author, Ian Back, wrote mPDF to output PDF files "on the fly" from his website and handle different languages. It is slower than original scripts like HTML2FPDF and produces larger files when using Unicode fonts, but supports CSS styles etc. and has a lot of enhancements. Supports almost all languages, including RTL (Arabic and Hebrew) and CJK (Chinese, Japanese and Korean). Supports nested block-level elements (such as P, DIV),

Dreamweaver CS6
Visual web development tools

VSCode Windows 64-bit Download
A free and powerful IDE editor launched by Microsoft

Atom editor mac version download
The most popular open source editor

Safe Exam Browser
Safe Exam Browser is a secure browser environment for taking online exams securely. This software turns any computer into a secure workstation. It controls access to any utility and prevents students from using unauthorized resources.
