Getting Started With Dash: Easy Data Visualization In Python - Part 1/3

A very common thing you want to do in Python is visualize your data in a dashboard. Today I show you how to set up data visualization using Plotly Dash in Python in a few easy steps. I'm going to revisit this example in a few weeks to add more features to the dashboard and to improve the design. A big thank you to Mark Todisco for his help with preparing the code example!

🔖 Chapters:
0:00 Intro
1:17 Explaining the example
2:41 Introduction to Dash
5:10 Setting up a Dash application
8:02 Adding a dropdown component
13:09 Adding a button to select all nations
14:31 Dash callbacks with inputs and outputs
17:21 Adding a bar chart
20:24 Connecting the dropdown with the bar chart
24:10 Showing a message if no data is selected
25:02 Analysis of the application setup

#arjancodes #softwaredesign #python

[vigneshmurali]

As someone who really likes your tutorials and shorts and a patron of this channel. If I can make a suggestion,
1. Whenever you talk about a specific module or a feature it would be better if you should something visual and do a voiceover. This is help people to understand what it is that you are exactly referring to at any point in time.
2. Before diving coding always provide with a good overview which can help people understand what it is that you are trying to do end to end. (Remember you may be knowing stuff beforehand but for the people who are watching you will need to have some context on what you are going to do).

Just some friendly suggestions.:) Cheers

[agar.iodestiny]

Just what I needed. Great video once again, you can't imagine the influence of your videos on a self-taught like me.
Your channel is a gold mine, and the content can't be found anywhere on the web. Can't thank you enough for your content. Thank you!!!

[kgrileyfyi]

Dude you really changed my life. Every since you taught me about the importance of python classes with dataclasses. All my sqlalchemy models became serialized with jsonify. I implemented the command pattern to generate pdfs and send invoices and I set up a transaction based accounting system. All your video have transformed my app in such a positive way. It feels like every video you post is a module that can be directly inserted in my app replacing my old code and vastly improving it into a way less coupled system. I just want to thank you because their is none of this stuff out there beside the content you are creating.

[luannguyen]

I work with data and really like using Dash. However I have been struggling with structuring a Dash project in a clean way. Thanks for sharing this, Arjan. Just what I needed.

[emonymph]

You earned a sub for actually slowing down for 15sec and explaining the terminology. "So for this we need a callback... A callback is..." Thank you! Most people would never define it. This means we can watch one of your videos and learn everything required to complete the task without having to search for other stuf. It means a lot!

[jdbmvmj]

Usually I do not tend to comment on videos but let me thank you for this gift of video!! You cannot imagine how much you helped me understand the way dash works - I am currently studying Data Science and this was great for making my data visualisation project where I analysed US accidents and their distribution over the different states. Thank you Arjan :))

[zachazares]

I remember watching this mini-series when it came out & enjoying the content. Now, months later after having made a dashboard used internally at my company, I rewatched & realized so many smelly parts of my code that your design has helped me refactor. Your content is so helpful & practical for learning good philosophies of code after the 1st, 2nd, & countless rewatches. Thank you for your entire channel Arjan!

[Plotly]

Awesome video, @ArjanCodes. Thank you for using Plotly and Dash and for teaching others.

[istvanmeszaros]

I agree with you about the Python magic. I think it causes more problems in this case than it actually helps.
Also without type hinting Dash apps easily become messy. Sometimes even with type hints, just try to change the return HTML instance to html.Span instead of a DIV,
not even mypy will complain. (At least this is my current experience)

However the lack of types and all this "magic" is very useful in notebooks for data analysts. So probably they should be only used there.
FYI, good thing that dash apps also work inside a notebook.

[ronalddebruijn]

Just in time this video! As a retired programmer, I started learning python just for fun. Looking for structure in the python world, I found your channel. It helps a lot. I like your pragmatic approach using classes and functional programming. Just now I started looking at Plotly and Dash. Again looking for structure, again provided by ArjanCodes..

[warrenarmstrong]

Thank you for covering this topic Arjan!

[MarvinAustria]

Love it! First time working with Dash and I love your explanation! Thank you

[izem]

You can use the query method with f-strings if you want to reference to the 'nations' variable: MEDAL_DATA.query(f"nation in {nations})")

[antoniocarlossegurogonzale]

Right when I needed this, thank you so much Arjan

[uticaburn]

I have programmed in Python for years, but honestly all new to me to see syntax like "from . import" and "->" in a function definition.
Some further studies needed to completely understand this tutorial.

[carecavoador]

Uow! This is so powerful and elegant! Thank you so much for this, Arjan.

[AsantePE]

Beste Arjan heel veel succes, dit is een toffe tutorial.

[PeterSeres]

Great video. Some feedback though on the video design: going from a dark setup to an all-white webpage is really jarring and would appreciate in newer videos to keep a consistent dark / light theme.

[liucloud]

Your tutorials are always clear and concise! Thank you for sharing it, Arjun!

[uticaburn]

would you recommend first learning html?
coming from a python background and being new to HTML it seems like dash is structured in a way that takes HTML as a prerequisite