ggiraph presentation

David Gohel

2016-07-01

The ggiraph package let R users to make ggplot interactive. The package is an htmlwidget. Below an example:

It extends ggplot2 with new geom functions:

geom_bar_interactive
geom_point_interactive
geom_polygon_interactive
geom_map_interactive
geom_path_interactive
geom_rect_interactive
geom_segment_interactive
geom_text_interactive
geom_boxplot_interactive

Three arguments let you add interactivity:

tooltip: column of dataset that contains tooltips to be displayed when mouse is over elements.
onclick: column of dataset that contains javascript function to be executed when elements are clicked.
data_id: column of dataset that contains id to be associated with elements.

Let’s prepare a ggplot object with mpg dataset.

library(ggiraph)

head(mpg)

##   manufacturer model displ year cyl      trans drv cty hwy fl   class
## 1         audi    a4   1.8 1999   4   auto(l5)   f  18  29  p compact
## 2         audi    a4   1.8 1999   4 manual(m5)   f  21  29  p compact
## 3         audi    a4   2.0 2008   4 manual(m6)   f  20  31  p compact
## 4         audi    a4   2.0 2008   4   auto(av)   f  21  30  p compact
## 5         audi    a4   2.8 1999   6   auto(l5)   f  16  26  p compact
## 6         audi    a4   2.8 1999   6 manual(m5)   f  18  26  p compact

g <- ggplot(mpg, aes( x = displ, y = cty, color = drv) ) + theme_minimal()

tooltips

The first example show how to add tooltip:

my_gg <- g + geom_point_interactive(aes(tooltip = model), size = 2) 
ggiraph(code = print(my_gg), width = .7)

hover effects

Now let’s add an hover effect. Elements associated with a data_id will be animated when mouse will be hover.

my_gg <- g + geom_point_interactive(
    aes(tooltip = model, data_id = model), size = 2) 
ggiraph(code = print(my_gg), width = .7)

Default value of hover css is hover_css = "fill:orange;". To see how to change that, read the custome_effects vignette.

Note that data-id can also be reused within a shiny application.

Click actions

Click actions must be a string column in the dataset containing valid javascript instructions.

crimes <- data.frame(state = tolower(rownames(USArrests)), USArrests)
head(crimes)

##                 state Murder Assault UrbanPop Rape
## Alabama       alabama   13.2     236       58 21.2
## Alaska         alaska   10.0     263       48 44.5
## Arizona       arizona    8.1     294       80 31.0
## Arkansas     arkansas    8.8     190       50 19.5
## California california    9.0     276       91 40.6
## Colorado     colorado    7.9     204       78 38.7

# create an 'onclick' column
crimes$onclick <- sprintf("window.open(\"%s%s\")",
  "http://en.wikipedia.org/wiki/", as.character(crimes$state) )

gg_crime <- ggplot(crimes, aes(x = Murder, y = Assault, color = UrbanPop )) + 
  geom_point_interactive(
    aes( data_id = state, tooltip = state, onclick = onclick ), size = 3 ) + 
  scale_colour_gradient(low = "#999999", high = "#FF3333") + 
  theme_minimal()

ggiraph(code = print(gg_crime),
        hover_css = "fill-opacity:.3;cursor:pointer;")

Zoom

You can activate zoom; set zoom_max (maximum zoom factor) to a value greater than 1.

ggiraph(code = print(my_gg + theme_linedraw()), zoom_max = 5)