A stacked area chart displays the evolution of a numeric variable for several groups. It is very close to a area chart. This section displays many examples build with R and ggplot2. Have a look to data-to-viz.com if want to learn more about line chart theory.
This section is tightly linked with other sections. A line chart is the same but doesn't fill the surface between the line and the X axis. A connected scatterplot is almost the same thing, but each observation is represented as a dot. More generally, the time series section can interest you.connected scatter line chart time series
Drawing a stacked area chart with
ggplot2 is pretty straightforward once you've understood how to build an area chart with
geom_area(). Basically, you just have to provide a categorical to the
fill argument to split the area by groups.
Most basic stacked area chart you can build with R and ggplot2, using the geom_area function.
ggplotly() function of the
plotly library makes it a breeze to build an interactive version. Try to hover circles to get a tooltip, or select an area of interest for zooming. Double click to reinitialize.
Stacking suffers several issues. In the left chart below, try to estimate how the green group evolved during the period? You can read more about this acaveat here. Depending what your final goal is, it can be better to use small multiple or unstacked line chart.Learn more
The issue with stacking.
Try to understand how the green group evolved on the period. Pretty hard isn't it?
dygraph package is dedicated to time series visualization. It offers zooming, hovering, minimaps and much more. Visit the time series section that is dedicated to it for more.
In base R, the combination of the
plot() and the
polygon() functions allows to build quality area charts.
The web is full of astonishing R charts made by awesome bloggers. The R graph gallery tries to display some of the best creations and explain how their source code works. If you want to display your work here, please drop me a word or even better, submit a Pull Request!
Line chart with labels
It is a common need to display labels at the end of the lines, since that's the place where labels are the more readable. Cédric Scherer gives us a nice walk-through here on how to do it with ggplot2.