The python usage of len function is: 1. String, len() function returns the length of the string, that is, the number of characters; 2. List, len() function returns the number of items in the list, that is, the number of elements in it Number; 3. Tuple, the len() function returns the number of items of the tuple, that is, the number of elements in it; 4. Dictionary, the len() function returns the number of items of the dictionary, that is, the number of key-value pairs, etc.
# Operating system for this tutorial: Windows 10 system, Dell G3 computer.
In Python, the len() function is used to return the length or number of items of an object (such as string, list, tuple, etc.).
The following are some example usages of the len() function:
String:
text = "Hello, World!" print(len(text)) # 输出:13
In this example, the len() function returns characters The length of the string "Hello, World!", that is, the number of characters.
List:
my_list = [1, 2, 3, 4, 5] print(len(my_list)) # 输出:5
In this example, the len() function returns the number of items in the list [1, 2, 3, 4, 5], which is The number of elements.
Tuple:
my_tuple = (1, 2, 3) print(len(my_tuple)) # 输出:3
In this example, the len() function returns the number of items in the tuple (1, 2, 3), that is, the number of elements in it number.
Dictionary:
my_dict = {"apple": 1, "banana": 2, "orange": 3} print(len(my_dict)) # 输出:3
In this example, the len() function returns the dictionary {"apple": 1, "banana": 2, "orange": 3 }The number of items, that is, the number of key-value pairs in it.
Please note that the len() function works for most objects, but if the object is not iterable (such as integers, floating point numbers, etc.), it will cause a TypeError exception.
The above is the detailed content of What is the usage of len function in Python?. For more information, please follow other related articles on the PHP Chinese website!

Pythonusesahybridapproach,combiningcompilationtobytecodeandinterpretation.1)Codeiscompiledtoplatform-independentbytecode.2)BytecodeisinterpretedbythePythonVirtualMachine,enhancingefficiencyandportability.

ThekeydifferencesbetweenPython's"for"and"while"loopsare:1)"For"loopsareidealforiteratingoversequencesorknowniterations,while2)"while"loopsarebetterforcontinuinguntilaconditionismetwithoutpredefinediterations.Un

In Python, you can connect lists and manage duplicate elements through a variety of methods: 1) Use operators or extend() to retain all duplicate elements; 2) Convert to sets and then return to lists to remove all duplicate elements, but the original order will be lost; 3) Use loops or list comprehensions to combine sets to remove duplicate elements and maintain the original order.

ThefastestmethodforlistconcatenationinPythondependsonlistsize:1)Forsmalllists,the operatorisefficient.2)Forlargerlists,list.extend()orlistcomprehensionisfaster,withextend()beingmorememory-efficientbymodifyinglistsin-place.

ToinsertelementsintoaPythonlist,useappend()toaddtotheend,insert()foraspecificposition,andextend()formultipleelements.1)Useappend()foraddingsingleitemstotheend.2)Useinsert()toaddataspecificindex,thoughit'sslowerforlargelists.3)Useextend()toaddmultiple

Pythonlistsareimplementedasdynamicarrays,notlinkedlists.1)Theyarestoredincontiguousmemoryblocks,whichmayrequirereallocationwhenappendingitems,impactingperformance.2)Linkedlistswouldofferefficientinsertions/deletionsbutslowerindexedaccess,leadingPytho

Pythonoffersfourmainmethodstoremoveelementsfromalist:1)remove(value)removesthefirstoccurrenceofavalue,2)pop(index)removesandreturnsanelementataspecifiedindex,3)delstatementremoveselementsbyindexorslice,and4)clear()removesallitemsfromthelist.Eachmetho

Toresolvea"Permissiondenied"errorwhenrunningascript,followthesesteps:1)Checkandadjustthescript'spermissionsusingchmod xmyscript.shtomakeitexecutable.2)Ensurethescriptislocatedinadirectorywhereyouhavewritepermissions,suchasyourhomedirectory.


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

SublimeText3 Linux new version
SublimeText3 Linux latest version

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),

SecLists
SecLists is the ultimate security tester's companion. It is a collection of various types of lists that are frequently used during security assessments, all in one place. SecLists helps make security testing more efficient and productive by conveniently providing all the lists a security tester might need. List types include usernames, passwords, URLs, fuzzing payloads, sensitive data patterns, web shells, and more. The tester can simply pull this repository onto a new test machine and he will have access to every type of list he needs.

Notepad++7.3.1
Easy-to-use and free code editor

MantisBT
Mantis is an easy-to-deploy web-based defect tracking tool designed to aid in product defect tracking. It requires PHP, MySQL and a web server. Check out our demo and hosting services.
