# Tutorials

Learn to visualize your data like an expert with these practical how-tos for presentation, analysis, and understanding.

#### Drawing Circles and Ellipses in R

Whether you use circles as visual encodings or as a way to highlight areas of a plot, there are functions at your disposal.

#### Drawing Squares and Rectangles in R

R makes it easy to add squares and rectangles to your plots, but it gets a little tricky when you have a bunch to draw at once. The key is to break it down to the elements.

#### Voronoi Diagram and Delaunay Triangulation in R

The

`deldir`

package by Rolf Turner makes the calculations and plotting straightforward, with a few lines of code. #### How to Make an Interactive Stacked Area Chart

Stacked area charts let you see categorical data over time. Interaction allows you to focus on specific categories without losing sight of the big picture.

#### How to Customize Axes in R

For presentation purposes, it can be useful to adjust the style of your axes and reference lines for readability. It's all about the details.

#### How to Make an Interactive Bar Chart With a Slider

Provide a slider for the standard bar chart so that users can shift focus to a point of interest.

#### Animated Pyramid Chart in R

Make a bunch of charts, string them together like a flip book, and there's your animation. Sometimes good for showing changes over time. Always fun to play with.

#### Bivariate Area Charts in R

Quickly compare two time series variables with this line-area chart hybrid that originated in the 1700s.

#### How to Make Maps in R That Include Alaska and Hawaii

The conterminous United States always gets the attention, while Alaska and Hawaii are often left out. It is time to bring them back into view.

#### How to Map and Use GeoTIFF Files in R

It's like working with a bunch of tiny dots, and oh look, all of sudden patterns emerge.

#### How to Make Horizon Graphs in R

The relatively new and lesser known time series visualization can be useful if you know what you're looking at, and they take up a lot less space.

#### How to Make Variable Width Bar Charts in R

The code to create these bar chart variations is almost the same as if you were to make a standard bar chart. But make sure you get the math right.

#### A Course for Visualization in R, Taking You From Beginner to Advanced

Where to start? What to learn next? Here's a course to help take you from beginner to advanced.