Text and Annotations in ggplot2

Adding annotations in ggplot2 with Plotly.

New to Plotly?

Plotly is a free and open-source graphing library for R. We recommend you read our Getting Started guide for the latest installation or upgrade instructions, then move on to our Plotly Fundamentals tutorials or dive straight in to some Basic Charts tutorials.

Default annotate

Set x and y position of the label.

library(plotly)

p <- ggplot(mtcars, aes(x = wt, y = mpg)) + geom_point()
p <-  p + annotate("text", x = 4, y = 25, label = "Some text")

plotly::ggplotly(p)

Usin range

library(plotly)

p <- ggplot(mtcars, aes(x = wt, y = mpg)) + geom_point()
p <-  p + annotate("text", x = 2:5, y = 25, label = "Some text")

plotly::ggplotly(p)

Creating rectangle

library(plotly)

p <- ggplot(mtcars, aes(x = wt, y = mpg)) + geom_point()
p <-    
 p + annotate("rect", xmin = 3, xmax = 4.2, ymin = 12, ymax = 21,
  alpha = .2)

plotly::ggplotly(p)

Creating segment

library(plotly)

p <- ggplot(mtcars, aes(x = wt, y = mpg)) + geom_point()
p <-    
 p + annotate("segment", x = 2.5, xend = 4, y = 15, yend = 25,
  colour = "blue")

plotly::ggplotly(p)

Creating pointrange

library(plotly)

p <- ggplot(mtcars, aes(x = wt, y = mpg)) + geom_point()
p <-    
 p + annotate("pointrange", x = 3.5, y = 20, ymin = 12, ymax = 28,
  colour = "red", size = 1.5)

plotly::ggplotly(p)

Adding multiple labels manually

library(plotly)

p <- ggplot(mtcars, aes(x = wt, y = mpg)) + geom_point()
p <-  p + annotate("text", x = 2:3, y = 20:21, label = c("my label", "label 2"))

plotly::ggplotly(p)

Stlying label text

library(plotly)

p <- ggplot(mtcars, aes(x = wt, y = mpg)) + geom_point()
p <-    
 p + annotate("text", x = 4, y = 25, label = "italic(R) ^ 2 == 0.75",
  parse = TRUE)

plotly::ggplotly(p)

library(plotly)

p <- ggplot(mtcars, aes(x = wt, y = mpg)) + geom_point()
p <-    
 p + annotate("text", x = 4, y = 25,
  label = "paste(italic(R) ^ 2, \" = .75\")", parse = TRUE)

plotly::ggplotly(p)

Default raster plot

Set anootation_raster at specific position.

library(plotly)

rainbow <- matrix(hcl(seq(0, 360, length.out = 50 * 50), 80, 70), nrow = 50)
p <-    
 ggplot(mtcars, aes(mpg, wt)) +
  geom_point() +
  annotation_raster(rainbow, 15, 20, 3, 4)

plotly::ggplotly(p)

Fill the whole raster plot

library(plotly)

rainbow <- matrix(hcl(seq(0, 360, length.out = 50 * 50), 80, 70), nrow = 50)
p <-    
 ggplot(mtcars, aes(mpg, wt)) +
  annotation_raster(rainbow, -Inf, Inf, -Inf, Inf) +
  geom_point()

plotly::ggplotly(p)

Sequential raster

library(plotly)

rainbow2 <- matrix(hcl(seq(0, 360, length.out = 10), 80, 70), nrow = 1)
p <-    
 ggplot(mtcars, aes(mpg, wt)) +
  annotation_raster(rainbow2, -Inf, Inf, -Inf, Inf) +
  geom_point()

plotly::ggplotly(p)

Interploate raster colours

library(plotly)

rainbow2 <- matrix(hcl(seq(0, 360, length.out = 10), 80, 70), nrow = 1)
p <-    
 ggplot(mtcars, aes(mpg, wt)) +
  annotation_raster(rainbow2, -Inf, Inf, -Inf, Inf, interpolate = TRUE) +
  geom_point()

plotly::ggplotly(p)

What About Dash?

Dash for R is an open-source framework for building analytical applications, with no Javascript required, and it is tightly integrated with the Plotly graphing library.

Learn about how to install Dash for R at https://dashr.plot.ly/installation.

Everywhere in this page that you see fig, you can display the same figure in a Dash for R application by passing it to the figure argument of the Graph component from the built-in dashCoreComponents package like this:

library(plotly)

fig <- plot_ly() 
# fig <- fig %>% add_trace( ... )
# fig <- fig %>% layout( ... ) 

library(dash)
library(dashCoreComponents)
library(dashHtmlComponents)

app <- Dash$new()
app$layout(
    htmlDiv(
        list(
            dccGraph(figure=fig) 
        )
     )
)

app$run_server(debug=TRUE, dev_tools_hot_reload=FALSE)