Python Multidimensional arrays

In python, you get to learn and implement a variety of things, including the python multidimensional arrays. Learn more about this here.

Python Multidimensional arrays: Lists in lists

Depending what you’re doing, you may not really have a 2-D array.

80% of the time you have simple list of “row-like objects”, which might be proper sequences.

myArray = [ ('pi',3.14159,'r',2), ('e',2.71828,'theta',.5) ] myArray[0][1] == 3.14159 myArray[1][1] == 2.71828

More often, they’re instances of a class or a dictionary or a set or something more interesting that you didn’t have in your previous languages.

myArray = [ {'pi':3.1415925,'r':2}, {'e':2.71828,'theta':.5} ]

20% of the time you have a dictionary, keyed by a pair

myArray = { (2009,'aug'):(some,tuple,of,values), (2009,'sep'):(some,other,tuple) }

Rarely, will you actually need a matrix.

You have a large, large number of collection classes in Python. Odds are good that you have something more interesting than a matrix.

A good way to visualize a 2d array is as a list of lists. Something like this:

lst=[[1,2,3],[4,5,6],[7,8,9]]

here the outer list lst has three things in it. each of those things is another list: The first one is: [1,2,3], the second

one is: [4,5,6] and the third one is: [7,8,9]. You can access these lists the same way you would access another other element of a list, like this:

print (lst[0])

output: [1, 2, 3]

print (lst[1])

output: [4, 5, 6]

print (lst[2])

output: [7, 8, 9]

You can then access the different elements in each of those lists the same way:

print (lst[0][0])

output: 1

print (lst[0][1])

output: 2

Here the first number inside the [] brackets means get the list in that position. In the above example we used the number 0 to mean get the list in the 0th position which is [1,2,3]. The second set of [] brackets means get the item in that position from the inner list. In this case we used both 0 and 1 the 0th position in the list we got is the number 1 and in the 1st position it is 2

You can also set values inside these lists the same way:

lst[0]=[10,11,12]

Now the list is [[10,11,12],[4,5,6],[7,8,9]]. In this example we changed the whole first list to be a completely new list.

lst[1][2]=15

Now the list is [[10,11,12],[4,5,15],[7,8,9]]. In this example we changed a single element inside of one of the inner lists. First we went into the list at position 1 and changed the element within it at position 2, which was 6 now it’s 15.

Lists in lists in lists in..

This behaviour can be extended. Here is a 3-dimensional array:

[[[111,112,113],[121,122,123],[131,132,133]],[[211,212,213],[221,222,223],[231,232,233]],[[311,312, 313],[321,322,323],[331,332,333]]]

As is probably obvious, this gets a bit hard to read. Use backslashes to break up the different dimensions:

[[[111,112,113],[121,122,123],[131,132,133]],\
[[211,212,213],[221,222,223],[231,232,233]],\
[[311,312,313],[321,322,323],[331,332,333]]]

By nesting the lists like this, you can extend to arbitrarily high dimensions.

Accessing is similar to 2D arrays:

print(myarray)
print(myarray[1])
print(myarray[2][1])
print(myarray[1][0][2])

etc.

And editing is also similar:

myarray[1]=new_n-1_d_list
myarray[2][1]=new_n-2_d_list
myarray[1][0][2]=new_n-3_d_list #or a single number if you're dealing with 3D arrays etc.

More information:

Must Read Python Interview Questions

200+ Python Tutorials With Coding Examples

Python Language Basics TutorialPython String Representations of Class Instances
Python For Beginners TutorialPython Debugging Tutorial
Python Data Types TutorialReading and Writing CSV File Using Python
Python Indentation TutorialWriting to CSV in Python from String/List
Python Comments and Documentation TutorialPython Dynamic Code Execution Tutorial
Python Date And Time TutorialPython Code Distributing using Pyinstaller
Python Date Formatting TutorialPython Data Visualization Tutorial
Python Enum TutorialPython Interpreter Tutorial
Python Set TutorialPython Args and Kwargs
Python Mathematical Operators TutorialPython Garbage Collection Tutorial
Python Bitwise Operators TutorialPython Pickle Data Serialisation
Python Bolean Operators TutorialPython Binary Data Tutorial
Python Operator Precedance TutorialPython Idioms Tutorial
Python Variable Scope And Binding TutorialPython Data Serialization Tutorial
Python Conditionals TutorialPython Multiprocessing Tutorial
Python Comparisons TutorialPython Multithreading Tutorial
Python Loops TutorialPython Processes and Threads
Python Arrays TutorialPython Concurrency Tutorial
Python Multidimensional Arrays TutorialPython Parallel Computation Tutorial
Python List TutorialPython Sockets Module Tutorial
Python List Comprehensions TutorialPython Websockets Tutorial
Python List Slicing TutorialSockets Encryption Decryption in Python
Python Grouby() TutorialPython Networking Tutorial
Python Linked Lists TutorialPython http Server Tutorial
Linked List Node TutorialPython Flask Tutorial
Python Filter TutorialIntroduction to Rabbitmq using Amqpstorm Python
Python Heapq TutorialPython Descriptor Tutorial
Python Tuple TutorialPython Tempflile Tutorial
Python Basic Input And Output TutorialInput Subset and Output External Data Files using Pandas in Python
Python Files And Folders I/O TutorialUnzipping Files in Python Tutorial
Python os.path TutorialWorking with Zip Archives in Python
Python Iterables And Iterators Tutorialgzip in Python Tutorial
Python Functions TutorialStack in Python Tutorial
Defining Functions With List Arguments In PythonWorking with Global Interpreter Lock (GIL)
Functional Programming In PythonPython Deployment Tutorial
Partial Functions In PythonPython Logging Tutorial
Decorators Function In PythonPython Server Sent Events Tutorial
Python Classes TutorialPython Web Server Gateway Interface (WSGI)
Python Metaclasses TutorialPython Alternatives to Switch Statement
Python String Formatting TutorialPython Packing and Unpacking Tutorial
Python String Methods TutorialAccessing Python Sourcecode and Bytecode
Using Loops Within Functions In PythonPython Mixins Tutorial
Python Importing Modules TutorialPython Attribute Access Tutorial
Difference Betweeb Module And Package In PythonPython Arcpy Tutorial
Python Math Module TutorialPython Abstract Base Class Tutorial
Python Complex Math TutorialPython Plugin and Extension Classes
Python Collections Module TutorialPython Immutable Datatypes Tutorial
Python Operator Module TutorialPython Incompatibilities Moving from Python 2 to Python 3
Python JSON Module TutorialPython 2to3 Tool Tutorial
Python Sqlite3 Module TutorialNon-Official Python implementations
Python os Module TutorialPython Abstract Syntax Tree
Python Locale Module TutorialPython Unicode and Bytes
Python Itertools Module TutorialPython Serial Communication (pyserial)
Python Asyncio Module TutorialNeo4j and Cypher using Py2Neo
Python Random Module TutorialBasic Curses with Python
Python Functools Module TutorialTemplates in Python
Python dis Module TutorialPython Pillow
Python Base64 Module TutorialPython CLI subcommands with precise help output
Python Queue Module TutorialPython Database Access
Python Deque Module TutorialConnecting Python to SQL Server
Python Webbrowser Module TutorialPython and Excel
Python tkinter TutorialPython Turtle Graphics
Python pyautogui Module TutorialPython Persistence
Python Indexing And Slicing TutorialPython Design Patterns
Python Plotting With Matplotlib TutorialPython hashlib
Python Graph Tool TutorialCreating a Windows Service Using Python
Python Generators TutorialMutable vs Immutable (and Hashable) in Python
Python Reduce TutorialPython configparser
Python Map Function TutorialPython Optical Character Recognition
Python Exponentiation TutorialPython Virtual Environments
Python Searching TutorialPython Virtual Environment – virtualenv
Sorting Minimum And Maximum In PythonPython Virtual environment with virtualenvwrapper
Python Print Function TutorialCreate virtual environment with virtualenvwrapper in windows
Python Regular Expressions Regex TutorialPython sys Tutorial
Copying Data In Python TutorialChemPy – Python package
Python Context Managers (“with” Statement) TutorialPython pygame
Python Name Special Variable TutorialPython pyglet
Checking Path Existence And Permissions In PythonWorking with Audio in Python
Creating Python Packages TutorialPython pyaudio
Usage of pip Module In Python TutorialPython shelve
Python PyPi Package Manager TutorialIoT Programming with Python and Raspberry PI
Parsing Command Line Arguments In Pythonkivy – Cross-platform Python Framework for NUI Development
Python Subprocess Library TutorialPandas Transform
Python setup.py TutorialPython vs. JavaScript
Python Recursion TutorialCall Python from C#
Python Type Hints TutorialPython Writing Extensions
Python Exceptions TutorialPython Lex-Yacc
Raise Custom Exceptions In PythonPython Unit Testing
Python Commonwealth Exceptions TutorialPython py.test
Python urllib TutorialPython Profiling
Web Scraping With Python TutorialPython Speed of Program
Python HTML Parsing TutorialPython Performance Optimization
Manipulating XML In PythonPython Security and Cryptography
Python Requests Post TutorialSecure Shell Connection in Python
Python Distribution TutorialPython Anti Patterns
Python Property Objects TutorialPython Common Pitfalls
Python Overloading TutorialPython Hidden Features
Python Polymorphism TutorialPython For Machine Learning
Python Method Overriding TutorialPython Interview Questions And Answers For Experienced
Python User Defined Methods TutorialPython Coding Interview Questions And Answers
Python Programming Tutorials With Examples

Other Python Tutorials

Leave a Comment