2D Histogram Contour in R

How to create 2D Histogram Contour plots in R 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.

Basic 2D Histogram Contour

library(plotly)

s <- matrix(c(1, -.75, -.75, 1), ncol = 2)
obs <- mvtnorm::rmvnorm(500, sigma = s)

fig <- plot_ly(x = obs[,1], y = obs[,2]) 

fig <- fig %>%
  add_trace(type='histogram2dcontour')

fig

Styled 2D Histogram Contour

library(plotly)

cnt <- with(diamonds, table(cut, clarity))

fig <- plot_ly(diamonds, x = ~cut, y = ~clarity) 
fig <- fig %>%
  add_trace(
    type='histogram2dcontour',
    contours = list(
      showlabels = T,
      labelfont = list(
        family = 'Raleway',
        color = 'white'
      )
    ),
    hoverlabel = list(
      bgcolor = 'white',
      bordercolor = 'black',
      font = list(
        family = 'Raleway',
        color = 'black'
      )
    )
)

fig

2D Histogram Contour Subplot

library(plotly)

x <- rnorm(1000)
y <- rnorm(1000)
s <- subplot(
  plot_ly(x = x, color = I("black"), type = 'histogram'), 
  plotly_empty(), 
  plot_ly(x = x, y = y, type = 'histogram2dcontour', showscale = F), 
  plot_ly(y = y, color = I("black"), type = 'histogram'),
  nrows = 2, heights = c(0.2, 0.8), widths = c(0.8, 0.2), 
  shareX = TRUE, shareY = TRUE, titleX = FALSE, titleY = FALSE
)

fig <- layout(s, showlegend = FALSE)

fig

Reference

See https://plotly.com/r/reference/#histogram2dcontour for more information and options!

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)