Plotting tables alsongside charts in R

Occasionally I'd like to plot a table alongside a chart in R, e.g. to present summary statistics of the graph itself. Thanks to the gridExtra package this is quite straightforward. The function tableGrob creates a table like plot of a data frame, while arrangeGrob allows me to arrange ggplot2, lattice and grid graphical objects (short 'grobs', such as tableGrob) on a page.

Here is a little example:

	# Create some sample data
	CV_1 <- 0.2
	CV_2 <- 0.3
	Mean <- 65
	sigma_1 <- sqrt(log(1 + CV_1^2))
	mu_1 <- log(Mean) - sigma_1^2 / 2
	sigma_2 <- sqrt(log(1 + CV_2^2))
	mu_2 <- log(Mean) - sigma_2^2 / 2
	q <- c(0.25, 0.5, 0.75, 0.9, 0.95)
	SummaryTable <- data.frame(
	Quantile=paste0(100*q,"%ile"),
	Loss_1=round(qlnorm(q, mu_1, sigma_1),1),
	Loss_2=round(qlnorm(q, mu_2, sigma_2),1)
	)
	# Create a plot
	library(ggplot2)
	plt <- ggplot(data.frame(x=c(20, 150)), aes(x)) +
	stat_function(fun=function(x) dlnorm(x, mu_1, sigma_1),
	aes(colour="CV_1")) +
	stat_function(fun=function(x) dlnorm(x, mu_2, sigma_2),
	aes(colour="CV_2")) +
	scale_colour_discrete(name = "CV",
	labels=c(expression(CV[1]), expression(CV[2]))) +
	xlab("Loss") +
	ylab("Density") +
	ggtitle(paste0("Two log-normal distributions with same mean of ",
	Mean,", but different CVs"))
	# Create a table plot
	library(gridExtra)
	names(SummaryTable) <- c("Quantile",
	expression(Loss(CV[1])),
	expression(Loss(CV[2])))
	# Set theme to allow for plotmath expressions
	tt <- ttheme_default(colhead=list(fg_params = list(parse=TRUE)))
	tbl <- tableGrob(SummaryTable, rows=NULL, theme=tt)
	# Plot chart and table into one object
	grid.arrange(plt, tbl,
	nrow=2,
	as.table=TRUE,
	heights=c(3,1))

view raw Plot_chart_and_table.R hosted with ❤ by GitHub

Session Info

R version 3.2.1 (2015-06-18)
Platform: x86_64-apple-darwin13.4.0 (64-bit)
Running under: OS X 10.10.4 (Yosemite)

locale:
[1] en_GB.UTF-8/en_GB.UTF-8/en_GB.UTF-8/C/en_GB.UTF-8/en_GB.UTF-8

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods  
[7] base     

other attached packages:
[1] gridExtra_2.0.0 ggplot2_1.0.1  

loaded via a namespace (and not attached):
 [1] Rcpp_0.11.6      digest_0.6.8     MASS_7.3-42     
 [4] grid_3.2.1       plyr_1.8.3       gtable_0.1.2    
 [7] magrittr_1.5     scales_0.2.5     stringi_0.5-5   
[10] reshape2_1.4.1   proto_0.3-10     labeling_0.3    
[13] tools_3.2.1      stringr_1.0.0    munsell_0.4.2   
[16] colorspace_1.2-6

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