Drawflow: This Allow You to Create Data Flows Easily and Quickly

Drawflow

Demo

Simple flow library.

Drawflow allows you to create data flows easily and quickly.

Installing only a javascript library and with four lines of code.

LIVE DEMO

🎨 THEME EDIT GENERATOR

Table of contents

Features

  • Drag Nodes
  • Multiple Inputs / Outputs
  • Multiple connections
  • Delete Nodes and Connections
  • Add/Delete inputs/outputs
  • Reroute connections
  • Data sync on Nodes
  • Zoom in / out
  • Clear data module
  • Support modules
  • Editor mode edit, fixed or view
  • Import / Export data
  • Events
  • Mobile support
  • Vanilla javascript (No dependencies)
  • NPM
  • Vue Support component nodes && Nuxt

Installation

Download or clone repository and copy the dist folder, CDN option Or npm.

Clone

git clone https://github.com/jerosoler/Drawflow.git

CDN

<link rel="stylesheet" href="https://cdn.jsdelivr.net/gh/jerosoler/Drawflow/dist/drawflow.min.css">
<script src="https://cdn.jsdelivr.net/gh/jerosoler/Drawflow/dist/drawflow.min.js"></script>
# or
<link rel="stylesheet" href="https://unpkg.com/drawflow@0.0.45/dist/drawflow.min.css" />
<script src="https://unpkg.com/drawflow@0.0.45/dist/drawflow.min.js"></script>

NPM

npm i drawflow

Typescript

External package. More info #119

npm install -D @types/drawflow

Import

import Drawflow from 'drawflow'
import styleDrawflow from 'drawflow/dist/drawflow.min.css'

Require

var Drawflow = require('drawflow')
var styleDrawflow = require('drawflow/dist/drawflow.min.css')

Create the parent element of drawflow.

<div id="drawflow"></div>

Running

Start drawflow.

var id = document.getElementById("drawflow");
const editor = new Drawflow(id);
editor.start();
ParameterTypeDescription
idObjectName of module
renderObjectIt's for Vue.
parentObjectIt's for Vue. The parent Instance

For vue 2 example.

import Vue from 'vue'

// Pass render Vue
this.editor = new Drawflow(id, Vue, this);

For vue 3 example.

import { h, getCurrentInstance, render } from 'vue'
const Vue = { version: 3, h, render };

this.editor = new Drawflow(id, Vue);
// Pass render Vue 3 Instance
const internalInstance = getCurrentInstance()
editor.value = new Drawflow(id, Vue, internalInstance.appContext.app._context);

Nuxt

Add to nuxt.config.js file

build: {
    transpile: ['drawflow'],
    ...
  }

Mouse and Keys

  • del key to remove element.
  • Right click to show remove options (Mobile long press).
  • Left click press to move editor or node selected.
  • Ctrl + Mouse Wheel Zoom in/out (Mobile pinch).

Editor

You can change the editor to fixed type to block. Only editor can be moved. You can put it before start.

editor.editor_mode = 'edit'; // Default
editor.editor_mode = 'fixed'; // Only scroll

You can also adjust the zoom values.

editor.zoom_max = 1.6;
editor.zoom_min = 0.5;
editor.zoom_value = 0.1;

Editor options

ParameterTypeDefaultDescription
rerouteBooleanfalseActive reroute
reroute_fix_curvatureBooleanfalseFix adding points
curvatureNumber0.5Curvature
reroute_curvature_start_endNumber0.5Curvature reroute first point and las point
reroute_curvatureNumber0.5Curvature reroute
reroute_widthNumber6Width of reroute
line_pathNumber5Width of line
force_first_inputBooleanfalseForce the first input to drop the connection on top of the node
editor_modeTexteditedit for edit, fixed for nodes fixed but their input fields available, view for view only
zoomNumber1Default zoom
zoom_maxNumber1.6Default zoom max
zoom_minNumber0.5Default zoom min
zoom_valueNumber0.1Default zoom value update
zoom_last_valueNumber1Default zoom last value
draggable_inputsBooleantrueDrag nodes on click inputs
useuuidBooleanfalseUse UUID as node ID instead of integer index. Only affect newly created nodes, do not affect imported nodes

Reroute

Active reroute connections. Use before start or import.

editor.reroute = true;

Create point with double click on line connection. Double click on point for remove.

Modules

Separate your flows in different editors.

editor.addModule('nameNewModule');
editor.changeModule('nameNewModule');
editor.removeModule('nameModule');
// Default Module is Home
editor.changeModule('Home');

RemovedModule if it is in the same module redirects to the Home module

Nodes

Adding a node is simple.

editor.addNode(name, inputs, outputs, posx, posy, class, data, html);
ParameterTypeDescription
nametextName of module
inputsnumberNumber of de inputs
outputsnumberNumber of de outputs
pos_xnumberPosition on start node left
pos_ynumberPosition on start node top
classtextAdded classname to de node. Multiple classnames separated by space
datajsonData passed to node
htmltextHTML drawn on node or name of register node.
typenodeboolean & textDefault false, true for Object HTML, vue for vue

You can use the attribute df-* in inputs, textarea or select to synchronize with the node data and contenteditable.

Atrributs multiples parents support df-*-*...

Node example

var html = `
<div><input type="text" df-name></div>
`;
var data = { "name": '' };

editor.addNode('github', 0, 1, 150, 300, 'github', data, html);

Register Node

it's possible register nodes for reuse.

var html = document.createElement("div");
html.innerHTML =  "Hello Drawflow!!";
editor.registerNode('test', html);
// Use
editor.addNode('github', 0, 1, 150, 300, 'github', data, 'test', true);

// For vue
import component from '~/components/testcomponent.vue'
editor.registerNode('name', component, props, options);
// Use for vue
editor.addNode('github', 0, 1, 150, 300, 'github', data, 'name', 'vue');
ParameterTypeDescription
nametextName of module registered.
htmltextHTML to drawn or vue component.
propsjsonOnly for vue. Props of component. Not Required
optionsjsonOnly for vue. Options of component. Not Required

Methods

Other available functions.

MehtodDescription
zoom_in()Increment zoom +0.1
zoom_out()Decrement zoom -0.1
getNodeFromId(id)Get Info of node. Ex: id: 5
getNodesFromName(name)Return Array of nodes id. Ex: name: telegram
removeNodeId(id)Remove node. Ex id: node-x
updateNodeDataFromIdUpdate data element. Ex: 5, { name: 'Drawflow' }
addNodeInput(id)Add input to node. Ex id: 5
addNodeOutput(id)Add output to node. Ex id: 5
removeNodeInput(id, input_class)Remove input to node. Ex id: 5, input_2
removeNodeOutput(id, output_class)Remove output to node. Ex id: 5, output_2
addConnection(id_output, id_input, output_class, input_class)Add connection. Ex: 15,16,'output_1','input_1'
removeSingleConnection(id_output, id_input, output_class, input_class)Remove connection. Ex: 15,16,'output_1','input_1'
updateConnectionNodes(id)Update connections position from Node Ex id: node-x
removeConnectionNodeId(id)Remove node connections. Ex id: node-x
getModuleFromNodeId(id)Get name of module where is the id. Ex id: 5
clearModuleSelected()Clear data of module selected
clear()Clear all data of all modules and modules remove.

Methods example

editor.removeNodeId('node-4');

Events

You can detect events that are happening.

List of available events:

EventReturnDescription
nodeCreatedidid of Node
nodeRemovedidid of Node
nodeDataChangedidid of Node df-* attributes changed.
nodeSelectedidid of Node
nodeUnselectedtrueUnselect node
nodeMovedidid of Node
connectionStart{ output_id, output_class }id of nodes and output selected
connectionCanceltrueConnection Cancel
connectionCreated{ output_id, input_id, output_class, input_class }id's of nodes and output/input selected
connectionRemoved{ output_id, input_id, output_class, input_class }id's of nodes and output/input selected
connectionSelected{ output_id, input_id, output_class, input_class }id's of nodes and output/input selected
connectionUnselectedtrueUnselect connection
addRerouteidid of Node output
removeRerouteidid of Node output
rerouteMovedidid of Node output
moduleCreatednamename of Module
moduleChangednamename of Module
moduleRemovednamename of Module
clickeventClick event
clickEndeventOnce the click changes have been made
contextmenueventClick second button mouse event
mouseMove{ x, y }Position
mouseUpeventMouseUp Event
keydowneventKeydown event
zoomzoom_levelLevel of zoom
translate{ x, y }Position translate editor
importimportFinish import
exportdataData export

Events example

editor.on('nodeCreated', function(id) {
  console.log("Node created " + id);
})

Export / Import

You can export and import your data.

var exportdata = editor.export();
editor.import(exportdata);

Export example

Example of exported data:

{
    "drawflow": {
        "Home": {
            "data": {}
        },
        "Other": {
            "data": {
                "16": {
                    "id": 16,
                    "name": "facebook",
                    "data": {},
                    "class": "facebook",
                    "html": "\n        
\n          
 Facebook Message
\n        
\n        ",
                    "inputs": {},
                    "outputs": {
                        "output_1": {
                            "connections": [
                                {
                                    "node": "17",
                                    "output": "input_1"
                                }
                            ]
                        }
                    },
                    "pos_x": 226,
                    "pos_y": 138
                },
                "17": {
                    "id": 17,
                    "name": "log",
                    "data": {},
                    "class": "log",
                    "html": "\n            
\n              
 Save log file
\n            
\n            ",
                    "inputs": {
                        "input_1": {
                            "connections": [
                                {
                                    "node": "16",
                                    "input": "output_1"
                                }
                            ]
                        }
                    },
                    "outputs": {},
                    "pos_x": 690,
                    "pos_y": 129
                }
            }
        }
    }
}

Example

View the complete example in folder docs.
There is also an example how to use Drawflow in a custom element. (based on LitElement).

Author: Jerosoler
Source Code: https://github.com/jerosoler/Drawflow 
License: MIT License

#javascript #flow #library 

What is GEEK

Buddha Community

Drawflow: This Allow You to Create Data Flows Easily and Quickly
Easter  Deckow

Easter Deckow

1655630160

PyTumblr: A Python Tumblr API v2 Client

PyTumblr

Installation

Install via pip:

$ pip install pytumblr

Install from source:

$ git clone https://github.com/tumblr/pytumblr.git
$ cd pytumblr
$ python setup.py install

Usage

Create a client

A pytumblr.TumblrRestClient is the object you'll make all of your calls to the Tumblr API through. Creating one is this easy:

client = pytumblr.TumblrRestClient(
    '<consumer_key>',
    '<consumer_secret>',
    '<oauth_token>',
    '<oauth_secret>',
)

client.info() # Grabs the current user information

Two easy ways to get your credentials to are:

  1. The built-in interactive_console.py tool (if you already have a consumer key & secret)
  2. The Tumblr API console at https://api.tumblr.com/console
  3. Get sample login code at https://api.tumblr.com/console/calls/user/info

Supported Methods

User Methods

client.info() # get information about the authenticating user
client.dashboard() # get the dashboard for the authenticating user
client.likes() # get the likes for the authenticating user
client.following() # get the blogs followed by the authenticating user

client.follow('codingjester.tumblr.com') # follow a blog
client.unfollow('codingjester.tumblr.com') # unfollow a blog

client.like(id, reblogkey) # like a post
client.unlike(id, reblogkey) # unlike a post

Blog Methods

client.blog_info(blogName) # get information about a blog
client.posts(blogName, **params) # get posts for a blog
client.avatar(blogName) # get the avatar for a blog
client.blog_likes(blogName) # get the likes on a blog
client.followers(blogName) # get the followers of a blog
client.blog_following(blogName) # get the publicly exposed blogs that [blogName] follows
client.queue(blogName) # get the queue for a given blog
client.submission(blogName) # get the submissions for a given blog

Post Methods

Creating posts

PyTumblr lets you create all of the various types that Tumblr supports. When using these types there are a few defaults that are able to be used with any post type.

The default supported types are described below.

  • state - a string, the state of the post. Supported types are published, draft, queue, private
  • tags - a list, a list of strings that you want tagged on the post. eg: ["testing", "magic", "1"]
  • tweet - a string, the string of the customized tweet you want. eg: "Man I love my mega awesome post!"
  • date - a string, the customized GMT that you want
  • format - a string, the format that your post is in. Support types are html or markdown
  • slug - a string, the slug for the url of the post you want

We'll show examples throughout of these default examples while showcasing all the specific post types.

Creating a photo post

Creating a photo post supports a bunch of different options plus the described default options * caption - a string, the user supplied caption * link - a string, the "click-through" url for the photo * source - a string, the url for the photo you want to use (use this or the data parameter) * data - a list or string, a list of filepaths or a single file path for multipart file upload

#Creates a photo post using a source URL
client.create_photo(blogName, state="published", tags=["testing", "ok"],
                    source="https://68.media.tumblr.com/b965fbb2e501610a29d80ffb6fb3e1ad/tumblr_n55vdeTse11rn1906o1_500.jpg")

#Creates a photo post using a local filepath
client.create_photo(blogName, state="queue", tags=["testing", "ok"],
                    tweet="Woah this is an incredible sweet post [URL]",
                    data="/Users/johnb/path/to/my/image.jpg")

#Creates a photoset post using several local filepaths
client.create_photo(blogName, state="draft", tags=["jb is cool"], format="markdown",
                    data=["/Users/johnb/path/to/my/image.jpg", "/Users/johnb/Pictures/kittens.jpg"],
                    caption="## Mega sweet kittens")

Creating a text post

Creating a text post supports the same options as default and just a two other parameters * title - a string, the optional title for the post. Supports markdown or html * body - a string, the body of the of the post. Supports markdown or html

#Creating a text post
client.create_text(blogName, state="published", slug="testing-text-posts", title="Testing", body="testing1 2 3 4")

Creating a quote post

Creating a quote post supports the same options as default and two other parameter * quote - a string, the full text of the qote. Supports markdown or html * source - a string, the cited source. HTML supported

#Creating a quote post
client.create_quote(blogName, state="queue", quote="I am the Walrus", source="Ringo")

Creating a link post

  • title - a string, the title of post that you want. Supports HTML entities.
  • url - a string, the url that you want to create a link post for.
  • description - a string, the desciption of the link that you have
#Create a link post
client.create_link(blogName, title="I like to search things, you should too.", url="https://duckduckgo.com",
                   description="Search is pretty cool when a duck does it.")

Creating a chat post

Creating a chat post supports the same options as default and two other parameters * title - a string, the title of the chat post * conversation - a string, the text of the conversation/chat, with diablog labels (no html)

#Create a chat post
chat = """John: Testing can be fun!
Renee: Testing is tedious and so are you.
John: Aw.
"""
client.create_chat(blogName, title="Renee just doesn't understand.", conversation=chat, tags=["renee", "testing"])

Creating an audio post

Creating an audio post allows for all default options and a has 3 other parameters. The only thing to keep in mind while dealing with audio posts is to make sure that you use the external_url parameter or data. You cannot use both at the same time. * caption - a string, the caption for your post * external_url - a string, the url of the site that hosts the audio file * data - a string, the filepath of the audio file you want to upload to Tumblr

#Creating an audio file
client.create_audio(blogName, caption="Rock out.", data="/Users/johnb/Music/my/new/sweet/album.mp3")

#lets use soundcloud!
client.create_audio(blogName, caption="Mega rock out.", external_url="https://soundcloud.com/skrillex/sets/recess")

Creating a video post

Creating a video post allows for all default options and has three other options. Like the other post types, it has some restrictions. You cannot use the embed and data parameters at the same time. * caption - a string, the caption for your post * embed - a string, the HTML embed code for the video * data - a string, the path of the file you want to upload

#Creating an upload from YouTube
client.create_video(blogName, caption="Jon Snow. Mega ridiculous sword.",
                    embed="http://www.youtube.com/watch?v=40pUYLacrj4")

#Creating a video post from local file
client.create_video(blogName, caption="testing", data="/Users/johnb/testing/ok/blah.mov")

Editing a post

Updating a post requires you knowing what type a post you're updating. You'll be able to supply to the post any of the options given above for updates.

client.edit_post(blogName, id=post_id, type="text", title="Updated")
client.edit_post(blogName, id=post_id, type="photo", data="/Users/johnb/mega/awesome.jpg")

Reblogging a Post

Reblogging a post just requires knowing the post id and the reblog key, which is supplied in the JSON of any post object.

client.reblog(blogName, id=125356, reblog_key="reblog_key")

Deleting a post

Deleting just requires that you own the post and have the post id

client.delete_post(blogName, 123456) # Deletes your post :(

A note on tags: When passing tags, as params, please pass them as a list (not a comma-separated string):

client.create_text(blogName, tags=['hello', 'world'], ...)

Getting notes for a post

In order to get the notes for a post, you need to have the post id and the blog that it is on.

data = client.notes(blogName, id='123456')

The results include a timestamp you can use to make future calls.

data = client.notes(blogName, id='123456', before_timestamp=data["_links"]["next"]["query_params"]["before_timestamp"])

Tagged Methods

# get posts with a given tag
client.tagged(tag, **params)

Using the interactive console

This client comes with a nice interactive console to run you through the OAuth process, grab your tokens (and store them for future use).

You'll need pyyaml installed to run it, but then it's just:

$ python interactive-console.py

and away you go! Tokens are stored in ~/.tumblr and are also shared by other Tumblr API clients like the Ruby client.

Running tests

The tests (and coverage reports) are run with nose, like this:

python setup.py test

Author: tumblr
Source Code: https://github.com/tumblr/pytumblr
License: Apache-2.0 license

#python #api 

Jenny Jabde

1621251999

Quick Flow Male Enhancement Reviews, Benefits Price & Buy Quick Flow?

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Your Data Architecture: Simple Best Practices for Your Data Strategy

If you accumulate data on which you base your decision-making as an organization, you should probably think about your data architecture and possible best practices.

If you accumulate data on which you base your decision-making as an organization, you most probably need to think about your data architecture and consider possible best practices. Gaining a competitive edge, remaining customer-centric to the greatest extent possible, and streamlining processes to get on-the-button outcomes can all be traced back to an organization’s capacity to build a future-ready data architecture.

In what follows, we offer a short overview of the overarching capabilities of data architecture. These include user-centricity, elasticity, robustness, and the capacity to ensure the seamless flow of data at all times. Added to these are automation enablement, plus security and data governance considerations. These points from our checklist for what we perceive to be an anticipatory analytics ecosystem.

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Gerhard  Brink

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Getting Started With Data Lakes

Frameworks for Efficient Enterprise Analytics

The opportunities big data offers also come with very real challenges that many organizations are facing today. Often, it’s finding the most cost-effective, scalable way to store and process boundless volumes of data in multiple formats that come from a growing number of sources. Then organizations need the analytical capabilities and flexibility to turn this data into insights that can meet their specific business objectives.

This Refcard dives into how a data lake helps tackle these challenges at both ends — from its enhanced architecture that’s designed for efficient data ingestion, storage, and management to its advanced analytics functionality and performance flexibility. You’ll also explore key benefits and common use cases.

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As technology continues to evolve with new data sources, such as IoT sensors and social media churning out large volumes of data, there has never been a better time to discuss the possibilities and challenges of managing such data for varying analytical insights. In this Refcard, we dig deep into how data lakes solve the problem of storing and processing enormous amounts of data. While doing so, we also explore the benefits of data lakes, their use cases, and how they differ from data warehouses (DWHs).


This is a preview of the Getting Started With Data Lakes Refcard. To read the entire Refcard, please download the PDF from the link above.

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Tamale  Moses

Tamale Moses

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Exploring Mutable and Immutable in Python

In this Python article, let's learn about Mutable and Immutable in Python. 

Mutable and Immutable in Python

Mutable is a fancy way of saying that the internal state of the object is changed/mutated. So, the simplest definition is: An object whose internal state can be changed is mutable. On the other hand, immutable doesn’t allow any change in the object once it has been created.

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Mutable Definition

Mutable is when something is changeable or has the ability to change. In Python, ‘mutable’ is the ability of objects to change their values. These are often the objects that store a collection of data.

Immutable Definition

Immutable is the when no change is possible over time. In Python, if the value of an object cannot be changed over time, then it is known as immutable. Once created, the value of these objects is permanent.

List of Mutable and Immutable objects

Objects of built-in type that are mutable are:

  • Lists
  • Sets
  • Dictionaries
  • User-Defined Classes (It purely depends upon the user to define the characteristics) 

Objects of built-in type that are immutable are:

  • Numbers (Integer, Rational, Float, Decimal, Complex & Booleans)
  • Strings
  • Tuples
  • Frozen Sets
  • User-Defined Classes (It purely depends upon the user to define the characteristics)

Object mutability is one of the characteristics that makes Python a dynamically typed language. Though Mutable and Immutable in Python is a very basic concept, it can at times be a little confusing due to the intransitive nature of immutability.

Objects in Python

In Python, everything is treated as an object. Every object has these three attributes:

  • Identity – This refers to the address that the object refers to in the computer’s memory.
  • Type – This refers to the kind of object that is created. For example- integer, list, string etc. 
  • Value – This refers to the value stored by the object. For example – List=[1,2,3] would hold the numbers 1,2 and 3

While ID and Type cannot be changed once it’s created, values can be changed for Mutable objects.

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Mutable Objects in Python

I believe, rather than diving deep into the theory aspects of mutable and immutable in Python, a simple code would be the best way to depict what it means in Python. Hence, let us discuss the below code step-by-step:

#Creating a list which contains name of Indian cities  

cities = [‘Delhi’, ‘Mumbai’, ‘Kolkata’]

# Printing the elements from the list cities, separated by a comma & space

for city in cities:
		print(city, end=’, ’)

Output [1]: Delhi, Mumbai, Kolkata

#Printing the location of the object created in the memory address in hexadecimal format

print(hex(id(cities)))

Output [2]: 0x1691d7de8c8

#Adding a new city to the list cities

cities.append(‘Chennai’)

#Printing the elements from the list cities, separated by a comma & space 

for city in cities:
	print(city, end=’, ’)

Output [3]: Delhi, Mumbai, Kolkata, Chennai

#Printing the location of the object created in the memory address in hexadecimal format

print(hex(id(cities)))

Output [4]: 0x1691d7de8c8

The above example shows us that we were able to change the internal state of the object ‘cities’ by adding one more city ‘Chennai’ to it, yet, the memory address of the object did not change. This confirms that we did not create a new object, rather, the same object was changed or mutated. Hence, we can say that the object which is a type of list with reference variable name ‘cities’ is a MUTABLE OBJECT.

Let us now discuss the term IMMUTABLE. Considering that we understood what mutable stands for, it is obvious that the definition of immutable will have ‘NOT’ included in it. Here is the simplest definition of immutable– An object whose internal state can NOT be changed is IMMUTABLE.

Again, if you try and concentrate on different error messages, you have encountered, thrown by the respective IDE; you use you would be able to identify the immutable objects in Python. For instance, consider the below code & associated error message with it, while trying to change the value of a Tuple at index 0. 

#Creating a Tuple with variable name ‘foo’

foo = (1, 2)

#Changing the index[0] value from 1 to 3

foo[0] = 3
	
TypeError: 'tuple' object does not support item assignment 

Immutable Objects in Python

Once again, a simple code would be the best way to depict what immutable stands for. Hence, let us discuss the below code step-by-step:

#Creating a Tuple which contains English name of weekdays

weekdays = ‘Sunday’, ‘Monday’, ‘Tuesday’, ‘Wednesday’, ‘Thursday’, ‘Friday’, ‘Saturday’

# Printing the elements of tuple weekdays

print(weekdays)

Output [1]:  (‘Sunday’, ‘Monday’, ‘Tuesday’, ‘Wednesday’, ‘Thursday’, ‘Friday’, ‘Saturday’)

#Printing the location of the object created in the memory address in hexadecimal format

print(hex(id(weekdays)))

Output [2]: 0x1691cc35090

#tuples are immutable, so you cannot add new elements, hence, using merge of tuples with the # + operator to add a new imaginary day in the tuple ‘weekdays’

weekdays  +=  ‘Pythonday’,

#Printing the elements of tuple weekdays

print(weekdays)

Output [3]: (‘Sunday’, ‘Monday’, ‘Tuesday’, ‘Wednesday’, ‘Thursday’, ‘Friday’, ‘Saturday’, ‘Pythonday’)

#Printing the location of the object created in the memory address in hexadecimal format

print(hex(id(weekdays)))

Output [4]: 0x1691cc8ad68

This above example shows that we were able to use the same variable name that is referencing an object which is a type of tuple with seven elements in it. However, the ID or the memory location of the old & new tuple is not the same. We were not able to change the internal state of the object ‘weekdays’. The Python program manager created a new object in the memory address and the variable name ‘weekdays’ started referencing the new object with eight elements in it.  Hence, we can say that the object which is a type of tuple with reference variable name ‘weekdays’ is an IMMUTABLE OBJECT.

Also Read: Understanding the Exploratory Data Analysis (EDA) in Python

Where can you use mutable and immutable objects:

Mutable objects can be used where you want to allow for any updates. For example, you have a list of employee names in your organizations, and that needs to be updated every time a new member is hired. You can create a mutable list, and it can be updated easily.

Immutability offers a lot of useful applications to different sensitive tasks we do in a network centred environment where we allow for parallel processing. By creating immutable objects, you seal the values and ensure that no threads can invoke overwrite/update to your data. This is also useful in situations where you would like to write a piece of code that cannot be modified. For example, a debug code that attempts to find the value of an immutable object.

Watch outs:  Non transitive nature of Immutability:

OK! Now we do understand what mutable & immutable objects in Python are. Let’s go ahead and discuss the combination of these two and explore the possibilities. Let’s discuss, as to how will it behave if you have an immutable object which contains the mutable object(s)? Or vice versa? Let us again use a code to understand this behaviour–

#creating a tuple (immutable object) which contains 2 lists(mutable) as it’s elements

#The elements (lists) contains the name, age & gender 

person = (['Ayaan', 5, 'Male'], ['Aaradhya', 8, 'Female'])

#printing the tuple

print(person)

Output [1]: (['Ayaan', 5, 'Male'], ['Aaradhya', 8, 'Female'])

#printing the location of the object created in the memory address in hexadecimal format

print(hex(id(person)))

Output [2]: 0x1691ef47f88

#Changing the age for the 1st element. Selecting 1st element of tuple by using indexing [0] then 2nd element of the list by using indexing [1] and assigning a new value for age as 4

person[0][1] = 4

#printing the updated tuple

print(person)

Output [3]: (['Ayaan', 4, 'Male'], ['Aaradhya', 8, 'Female'])

#printing the location of the object created in the memory address in hexadecimal format

print(hex(id(person)))

Output [4]: 0x1691ef47f88

In the above code, you can see that the object ‘person’ is immutable since it is a type of tuple. However, it has two lists as it’s elements, and we can change the state of lists (lists being mutable). So, here we did not change the object reference inside the Tuple, but the referenced object was mutated.

Also Read: Real-Time Object Detection Using TensorFlow

Same way, let’s explore how it will behave if you have a mutable object which contains an immutable object? Let us again use a code to understand the behaviour–

#creating a list (mutable object) which contains tuples(immutable) as it’s elements

list1 = [(1, 2, 3), (4, 5, 6)]

#printing the list

print(list1)

Output [1]: [(1, 2, 3), (4, 5, 6)]

#printing the location of the object created in the memory address in hexadecimal format

print(hex(id(list1)))

Output [2]: 0x1691d5b13c8	

#changing object reference at index 0

list1[0] = (7, 8, 9)

#printing the list

Output [3]: [(7, 8, 9), (4, 5, 6)]

#printing the location of the object created in the memory address in hexadecimal format

print(hex(id(list1)))

Output [4]: 0x1691d5b13c8

As an individual, it completely depends upon you and your requirements as to what kind of data structure you would like to create with a combination of mutable & immutable objects. I hope that this information will help you while deciding the type of object you would like to select going forward.

Before I end our discussion on IMMUTABILITY, allow me to use the word ‘CAVITE’ when we discuss the String and Integers. There is an exception, and you may see some surprising results while checking the truthiness for immutability. For instance:
#creating an object of integer type with value 10 and reference variable name ‘x’ 

x = 10
 

#printing the value of ‘x’

print(x)

Output [1]: 10

#Printing the location of the object created in the memory address in hexadecimal format

print(hex(id(x)))

Output [2]: 0x538fb560

#creating an object of integer type with value 10 and reference variable name ‘y’

y = 10

#printing the value of ‘y’

print(y)

Output [3]: 10

#Printing the location of the object created in the memory address in hexadecimal format

print(hex(id(y)))

Output [4]: 0x538fb560

As per our discussion and understanding, so far, the memory address for x & y should have been different, since, 10 is an instance of Integer class which is immutable. However, as shown in the above code, it has the same memory address. This is not something that we expected. It seems that what we have understood and discussed, has an exception as well.

Quick checkPython Data Structures

Immutability of Tuple

Tuples are immutable and hence cannot have any changes in them once they are created in Python. This is because they support the same sequence operations as strings. We all know that strings are immutable. The index operator will select an element from a tuple just like in a string. Hence, they are immutable.

Exceptions in immutability

Like all, there are exceptions in the immutability in python too. Not all immutable objects are really mutable. This will lead to a lot of doubts in your mind. Let us just take an example to understand this.

Consider a tuple ‘tup’.

Now, if we consider tuple tup = (‘GreatLearning’,[4,3,1,2]) ;

We see that the tuple has elements of different data types. The first element here is a string which as we all know is immutable in nature. The second element is a list which we all know is mutable. Now, we all know that the tuple itself is an immutable data type. It cannot change its contents. But, the list inside it can change its contents. So, the value of the Immutable objects cannot be changed but its constituent objects can. change its value.

FAQs

1. Difference between mutable vs immutable in Python?

Mutable ObjectImmutable Object
State of the object can be modified after it is created.State of the object can’t be modified once it is created.
They are not thread safe.They are thread safe
Mutable classes are not final.It is important to make the class final before creating an immutable object.

2. What are the mutable and immutable data types in Python?

  • Some mutable data types in Python are:

list, dictionary, set, user-defined classes.

  • Some immutable data types are: 

int, float, decimal, bool, string, tuple, range.

3. Are lists mutable in Python?

Lists in Python are mutable data types as the elements of the list can be modified, individual elements can be replaced, and the order of elements can be changed even after the list has been created.
(Examples related to lists have been discussed earlier in this blog.)

4. Why are tuples called immutable types?

Tuple and list data structures are very similar, but one big difference between the data types is that lists are mutable, whereas tuples are immutable. The reason for the tuple’s immutability is that once the elements are added to the tuple and the tuple has been created; it remains unchanged.

A programmer would always prefer building a code that can be reused instead of making the whole data object again. Still, even though tuples are immutable, like lists, they can contain any Python object, including mutable objects.

5. Are sets mutable in Python?

A set is an iterable unordered collection of data type which can be used to perform mathematical operations (like union, intersection, difference etc.). Every element in a set is unique and immutable, i.e. no duplicate values should be there, and the values can’t be changed. However, we can add or remove items from the set as the set itself is mutable.

6. Are strings mutable in Python?

Strings are not mutable in Python. Strings are a immutable data types which means that its value cannot be updated.

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Original article source at: https://www.mygreatlearning.com

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