


1. Sort by dictionary value (default is ascending order)
x = {1:2, 3:4, 4 :3, 2:1, 0:0}
1. sorted_x = sorted(x.iteritems(), key=operator.itemgetter(1)) print sorted_x
Output result: [(0, 0), (2, 1), (1, 2), (4, 3), (3, 4)]
If you want to sort in descending order, you can specify reverse=True
2. sorted_x = sorted(x.iteritems(), key=operator.itemgetter(1), reverse=True) print sorted_x
Output result: [(3, 4), (4, 3), (1, 2), (2 , 1), (0, 0)]
2. Or directly use the reverse method of list to reverse the order of sorted_x
sorted_x.reverse()
3. The more common method is to use lambda expression
sorted_x = sorted(x.iteritems(), key=lambda x : x[1] ) print sorted_x
Output result: [(0, 0), (2, 1), (1, 2), (4, 3), (3, 4)]
orted_x = sorted( x.iteritems(), key=lambda x : x[1], reverse=True) print sorted_x
Output result: [(3, 4), (4, 3), (1, 2), (2, 1), (0, 0)]
The above is the detailed content of python how to sort a list by the values of a dictionary within the list. For more information, please follow other related articles on the PHP Chinese website!

InPython,youappendelementstoalistusingtheappend()method.1)Useappend()forsingleelements:my_list.append(4).2)Useextend()or =formultipleelements:my_list.extend(another_list)ormy_list =[4,5,6].3)Useinsert()forspecificpositions:my_list.insert(1,5).Beaware

The methods to debug the shebang problem include: 1. Check the shebang line to make sure it is the first line of the script and there are no prefixed spaces; 2. Verify whether the interpreter path is correct; 3. Call the interpreter directly to run the script to isolate the shebang problem; 4. Use strace or trusts to track the system calls; 5. Check the impact of environment variables on shebang.

Pythonlistscanbemanipulatedusingseveralmethodstoremoveelements:1)Theremove()methodremovesthefirstoccurrenceofaspecifiedvalue.2)Thepop()methodremovesandreturnsanelementatagivenindex.3)Thedelstatementcanremoveanitemorslicebyindex.4)Listcomprehensionscr

Pythonlistscanstoreanydatatype,includingintegers,strings,floats,booleans,otherlists,anddictionaries.Thisversatilityallowsformixed-typelists,whichcanbemanagedeffectivelyusingtypechecks,typehints,andspecializedlibrarieslikenumpyforperformance.Documenti

Pythonlistssupportnumerousoperations:1)Addingelementswithappend(),extend(),andinsert().2)Removingitemsusingremove(),pop(),andclear().3)Accessingandmodifyingwithindexingandslicing.4)Searchingandsortingwithindex(),sort(),andreverse().5)Advancedoperatio

Create multi-dimensional arrays with NumPy can be achieved through the following steps: 1) Use the numpy.array() function to create an array, such as np.array([[1,2,3],[4,5,6]]) to create a 2D array; 2) Use np.zeros(), np.ones(), np.random.random() and other functions to create an array filled with specific values; 3) Understand the shape and size properties of the array to ensure that the length of the sub-array is consistent and avoid errors; 4) Use the np.reshape() function to change the shape of the array; 5) Pay attention to memory usage to ensure that the code is clear and efficient.

BroadcastinginNumPyisamethodtoperformoperationsonarraysofdifferentshapesbyautomaticallyaligningthem.Itsimplifiescode,enhancesreadability,andboostsperformance.Here'showitworks:1)Smallerarraysarepaddedwithonestomatchdimensions.2)Compatibledimensionsare

ForPythondatastorage,chooselistsforflexibilitywithmixeddatatypes,array.arrayformemory-efficienthomogeneousnumericaldata,andNumPyarraysforadvancednumericalcomputing.Listsareversatilebutlessefficientforlargenumericaldatasets;array.arrayoffersamiddlegro


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

Atom editor mac version download
The most popular open source editor

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

Zend Studio 13.0.1
Powerful PHP integrated development environment

SublimeText3 English version
Recommended: Win version, supports code prompts!

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