Python-datastructures
"In computer science, a data structure is a data organization, management, and storage format that enables efficient access and modification. More precisely, a data structure is a collection of data values, the relationships among them, and the functions or operations that can be applied to the data."
-- source: Wikipedia
Python knows how to work with of several types of data structures without the need to import additional libraries. Sometimes you do need to import a library to provide support (e.g. json, csv, sql) but most of these are already available when you have python installed. In rare cases you may need to build or acquire a third-party library for data structure support.
In these pages we mainly look at the most common data structures in python:
Name | Examples | Details | Characteristic |
Tuple | ('January', 'February', 'March', 'April', 'May')
(2, 3, 5, 7, 11, 13, 17, 19, 23, 29) |
Once set, values cannot be changed
Referenced with index |
surrounded by one single open and closed parenthesis
elements separated by a comma Strings are enclosed by apostrophes or quotes |
List | [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14]
['red', 'green', 'orange', 'blue'] |
Values can be modified, added, deleted
Referenced with index |
surrounded by one single open and closed square bracket
elements separated by a comma Strings are enclosed by apostrophes or quotes |
Dictionary | {'Joe':02079343, 'Alice':010534045, 'Bob':01084523}
{'x':234, 'y':345, 'z':456} |
Values can be modified, added, deleted
Referenced with a key |
surrounded by one single open and closed curly brace
elements separated by a comma each element contains one key and one value key and value are separated by a colon key maybe a string or a number strings (key or value) are enclosed by quotes keys must be unique |
Set | ([1029, 1238, 7821, 4312, 2716]) | Once set, values cannot be modified
Set values can be added and removed Set may only contain unique values Unordered |
single square brackets surrounded by single parenthesis
elements separated by a comma strings are enclosed by apostrophes or quotes |
json | [{ "first": "Joe', "hobbies": "swimming, running" }
{ "first": "Carol', "hobbies": "cycling, climbing" }] |
Values can be modified, added, deleted
Referenced with a key |
surrounded by one single open and closed curly brace (1x record)
multiple records surrounded by one single square open and close bracket records surrounded by curly braces record elements separated by a comma each element contains one key and one value key and value are separated by a colon keys surrounded by double quotes strings are enclosed by apostrophes or quotes |
csv | silver,32423,joe bloggs,"8,5",023-32425634,,,type=1,f | once set, values cannot be modified | elements separated by a comma
one record per line elements enclosed by quotes if string contains a comma |