I used to think that making nice table in R is not worth the effort. However, after changing my mind for the billionth time on relatively large tables for a paper and do not wanting to reformat them again from scratch, I gave a try to the formattable package, and I liked it very much.

I post here some basic formats I learnt from the web.

Note: I usually work on remote servers with no/limited graphical capabilities (no X11, basically), and for me the formattable function doesn’t work. I use the format_table instead and write the html code to a file, which I then open. However, I never noticed differences in the behavior of format_table from what more expert users showed for fromattable.

Let’s create a table:

library(formattable)
library(knitr)
outfile<-"test.html"
data<-data.frame(id=1:10,x=round(rnorm(10,100,25)))
myhtml <- format_table(data)
write(myhtml,outfile)

This is the output

Ok. It’s a table. I want to change the fonts, the font size, AND format the cell based on their values. It’s possible, but it was not easy for me to find a way to do that. See my post on stackoverflow with link to the demo where formattable author showed how to do that.

I will create two formatters.

font_and_grad is changing the fonts and coloring the cells with a gradient of colors based on cell values.

font_and_bar is changing the fonts and coloring the cells with a bar of a given color, with bar length based on cell values.

font_and_grad <- formatter("span",
style = x ~ style(
display = "block",
direction = "rtl",
"border-radius" = "4px",
"padding-right" = "2px",
"background-color" = csscolor(gradient(as.numeric(x),min.color="yellow",max.color="darkorange")),
"font-family" = "verdana",
"font-size" = 10))

font_and_bar <-formatter("span",
style = x ~ style(
display = "inline-block",
direction = "rtl",
"border-radius" = "4px",
"padding-right" = "2px",
"background-color" = csscolor("lightgreen"),
width = percent(proportion(x)),
"font-family" = "verdana",
"font-size" = 10))

myhtml <- format_table(data, list(id=font_and_grad,x=font_and_bar))
write(myhtml,outfile)

Now, the only horrible thing left are the header fonts. I had troubles accomplishing this, and at the end I decided that I would simply change the html code.

myhtml<-gsub("
<th style=\"text-align:right","<th style=\"font-family: verdana; font-size: 10; text-align:right",myhtml)

write(myhtml,outfile)

Maybe not the best approach, but it worked! Another approach has been suggested on stackoverflow, but it wasn’t very well suited for me. As usual, comments and suggestions are welcome.