plotly

An R package for creating interactive web graphics via the open source JavaScript graphing library plotly.js.

Installation

Install from CRAN:

install.packages("plotly")

Or install the latest development version (on GitHub) via devtools:

devtools::install_github("ropensci/plotly")

NOTE: The CRAN version of plotly is designed to work with the CRAN version of ggplot2, but at least for the time being, we recommend using the development versions of both plotly and ggplot2 (devtools::install_github("hadley/ggplot2")).

Getting started

Web-based ggplot2 graphics

If you use ggplot2, ggplotly() converts your static plots to an interactive web-based version!

library(plotly)
g <- ggplot(faithful, aes(x = eruptions, y = waiting)) +
  stat_density_2d(aes(fill = ..level..), geom = "polygon") + 
  xlim(1, 6) + ylim(40, 100)
ggplotly(g)

By default, ggplotly() tries to replicate the static ggplot2 version exactly (before any interaction occurs), but sometimes you need greater control over the interactive behavior. The ggplotly() function itself has some convenient "high-level" arguments, such as dynamicTicks, which tells plotly.js to dynamically recompute axes, when appropriate. The style() function also comes in handy for modifying the underlying traces attributes used to generate the plot:

gg <- ggplotly(g, dynamicTicks = "y")
style(gg, hoveron = "points", hoverinfo = "x+y+text", hoverlabel = list(bgcolor = "white"))

Moreover, since ggplotly() returns a plotly object, you can apply essentially any function from the R package on that object. Some useful ones include layout() (for customizing the layout), add_traces() (and its higher-level add_*() siblings, for example add_polygons(), for adding new traces/data), subplot() (for combining multiple plotly objects), and plotly_json() (for inspecting the underlying JSON sent to plotly.js).

The ggplotly() function will also respect some "unofficial" ggplot2 aesthetics, namely text (for customizing the tooltip), frame (for creating animations), and ids (for ensuring sensible smooth transitions).

Using plotly without ggplot2

The plot_ly() function provides a more direct interface to plotly.js so you can leverage more specialized chart types (e.g., parallel coordinates or maps) or even some visualization that the ggplot2 API won't ever support (e.g., surface, mesh, trisurf, or sankey diagrams). The cheatsheet is a nice quick reference for this interface, but the plotly cookbook has more complete overview of the philosophy behind this "non-ggplot2" approach.

plot_ly(z = ~volcano, type = "surface")

Crosstalk support

The R package has special support for linking/highlighting/filtering views that is not (yet) available outside of the R package. This functionality is built upon the crosstalk package, which distinguishes between two event classes: select and filter. The plotly package interprets these classes in the following way:

1. Select: add new "selection" trace(s) (i.e., graphical marks) and dim the other traces. Some people refer to this as "brushing" or "highlighting".
2. Filter: retain "selection" trace(s), but remove other traces, and update the layout accordingly. Some people refer to this as "crossfilter" or "drill-down".

The following gif helps to demonstrate the difference -- see here for the code used to generate it.

Like other crosstalk enabled widgets, plotly responds to filter events, but you can't (yet) emit a filter event via direct manipulation of a plotly graph. Unlike (some) other crosstalk enabled widgets, plotly has advanced support for select (a much more broad class than filter) events, like persistent/dynamic brushing, brushing via indirect manipulation, and even ways to completely control the appearance new selection traces. In other words, these "special" brushing features work when linking multiple plotly graphs, but may not when linking to other crosstalk enabled widgets.

To date, this slide deck is the most comprehensive, yet somewhat thorough, walk-through of this framework, but the linking views without shiny chapter of the plotly book provides even more background. There are also numerous demos shipped with the package which provide nice examples (list all the demos via demo(package = "plotly")).

plotly's crosstalk functionality aims to provide tools for interactively exploring subsets of your data with a fixed definition from data to plot. If you need more flexibility, you can always embed crosstalk plots within a larger shiny app, or even access and respond to any plotly event within shiny, but adding shiny into the equation comes with a cost -- the result is no longer standalone HTML (harder to share/host) and linking views requires fairly sophicated knowledge/use of shiny's reactive programming framework.

Learn more

We have lots of examples on https://plot.ly/r/ and https://plot.ly/ggplot2/, but a more comprehensive review is also available at https://cpsievert.github.io/plotly_book/. I also have a number of slide decks that also have useful demos.

Contributing

Please read through our contributing guidelines. Included are directions for opening issues, asking questions, contributing changes to plotly, and our code of conduct.