❌ Dataviz Caveat Flashcards
👋 Hi! I hope you’re doing well on your side of the planet. Here, spring is finally peeking through. I’m writing this from a hammock, with a lazy cat napping beside me and my kid playing with flowers. Love it! ❤️ Anyway, you’re not here for daydreaming but to sharpen your dataviz skills, so let's get into it. Good chart !== bad chart I’ve been building charts and teaching dataviz for a while now, and one thing always strikes me: the same common mistakes pop up over and over. Some of them are...
3 days ago • 2 min read🔍 ggplot2 [un]charted
👋 Hi! I know, it’s not Saturday today 🙈.But this week is special to me because I’m launching my latest project!! Can I tell you the story? I love R About 13 years ago, I finished my master's degree in genetics and started working as a bioinformatician. I discovered the joy of data analysis and fell in love with the final step: building great charts. To document what I learned, I created the R Graph Gallery, a collection of chart examples with code and explanations. Examples are sorted by...
6 days ago • 2 min readChoropleth + Histogram = ❤️
👋 Hi! As you might know I try to share a little dataviz tips & inspiration on LinkedIn every day.And this week, one post really struck a chord: The Graph This map is a choropleth map. It shows the unemployment rate in Belgium. Originally created by Koen Van den Eeckhout in Tableau, my associate Joseph (co-teacher for our Matplotlib Journey course) recreated it in Python.Here is a glimpse of his iterative process. We like calling this an "Evolution of a Matplotlib". 🔗 Check out the code here!...
10 days ago • 2 min read⚡️ 0.3 seconds to make your code clean!
👋 Hi there! As a software engineer and educator, I spend a lot of time watching beginners write code. And one thing always stands out: how slow it can be. Not because of logic or bugs, but because of typing & formatting! So today I suggest we talk about formatters.Before we start, can you answer this tiny poll? You already use a formatter when you code: TRUE FALSE If you're not using one yet, it’s an easy win that will instantly boost your productivity. And if you already are, read on:...
17 days ago • 3 min read🍔 Unstack This: a new chart type you'll definitely use!
👋 Hi! Hope things are going great on your side of the world. Over here, life is pretty sweet: I'm writing this while sipping mint tea in Morocco, where my brother is getting married! ☀️🎉 Anyway, today I want to share something I love about the dataviz world: It's 2025, and somehow... We’re still inventing new chart types!Let me show you in just a few minutes as usual. 🤯 The trouble with stacking Stacked bar & area charts are everywhere. But they have a problem: they make it really hard to...
24 days ago • 2 min read☀️ Should you really Shine?
👋 Hi! Today’s the final step in my How the Web Works series! We started by exploring what HTML, CSS, and JavaScript are. Then we saw how to use these tools to create interactive graphs, even when working with R or Python. Finally, I showed how to host your work on GitHub Pages, turning it into a free mini-website. 🔥 Today, I want to tackle a tricky but crucial concept: ⚡️ Static vs Dynamic websites A static website is like the one we built last week. You write a simple HTML file (manually, or...
about 1 month ago • 3 min read🔥 One click, One website
👋 Hi there! Welcome to step #3 of my series on the essentials of the web for dataviz practicioners. In step 1, we learned that a website is essentially an HTML file with a bit of CSS and JS. In step 2, we discovered that the libraries you use in R and Python to create interactive graphs are just wrappers that generate the HTML for you. You're almost a web developer now! With tools like Quarto and Jupyter, you can embed those interactive charts in stunning HTML reports. Now, the question is:...
about 1 month ago • 3 min read💃 Let’s Bring Them to Life!
👋 Hi! Last week, I gave you the shortest explanation of how a graph on a website works. So now you know what HTML, CSS, SVG, and JavaScript are. 95% of you said you're interested in how the web works, so today I want to take it one step further and answer this question: ➡️ Can I make interactive graphs with R or Python, and how does it work? Short answer: yes. Both R and Python offer powerful libraries that let you build stunning interactive charts with just a few lines of code. In R, this...
about 2 months ago • 3 min read🌎 The mechanics of web-based charts
👋 Hi! Today, I suggest we go through the quickest introduction on how a website works. And more importantly, how a graph on a website is built.If you're interested, you can read a long-form version of this on the d3 graph gallery! If you enjoy charts (I guess you do 😀), chances are you’ve seen a ton of them on the web. So, it’s worth knowing just a tiny bit about how this magic happens! Let’s break it down: 1️⃣ HTML – The Foundation Try this: Create a file on your laptop and name it...
about 2 months ago • 3 min read📈 Timeseries + variation = ❤️
👋 Hi! This week, one of my LinkedIn posts gained some traction. It turns out that most people still default to simple line charts when visualizing temporal data. Line charts are great. But, there are many other alternatives that can bring out more insights depending on your data! So, let’s go through a few alternatives you can consider the next time you’re working with temporal data: 1️⃣ Streamgraph Less accurate, but it creates organic, beautiful shapes that are truly eye-catching.✨ Use it...
about 2 months ago • 3 min read