RMarkdown Kable width issues

Question

I am trying to create a table to hold some basic information using Kable in RMarkdown that will be generated in HTML, PDF, and Word. Here is the code I have

---
title: "test"
author: ''
date: "2015/03/24"
output:
 pdf_document:
 keep_tex: yes  
---

```{r kable1, echo=FALSE}
Variable <- c("VAR1", "VAR2", "VAR3", "VAR4")
Label <- c("LABEL", "A very       loooooooooooooooooooooooooooooooooooooooooooo     ooooooooooooooooooooooooooooooooooooooo nnnnnnngggggggg label yall", "LAB3", "LAB4")
Classification <- c("Type1", "Type2", "Type1", "Type1")
data <- data.frame(Variable, Label, Classification)
library(knitr)
kable(data)
```

```{r kable2, echo=FALSE}
Variable <- c("VAR1", "VAR2", "VAR3", "VAR4")
Label <- c("LABEL", "LabLE", "LAB3", "LAB4")
Classification <- c("Type1", "Type2", "Type1", "Type1")
data <- data.frame(Variable, Label, Classification)
library(knitr)
kable(data)
```

The HTML output is as follows. This is what I want. I like how the table fills out the html. However, when I produce PDF I get the following.

As we can see there are issues with the PDF, the first table runs off the page and the second does not fill up the entire width. I am, unfortunately, a n00b when it comes to R, Kable, and RMarkdown. Is there a way to set options on the kable table so that the PDF looks as nice as the HTML in terms of page placement and width? Thanks!

Answer 1

LaTeX will not break the long lines inside of a table cell for you -- or you should use a custom environment for that, which can be sometimes really frustrating when writing markdown to be processed by Pandoc. That's why I came up with the idea to break long lines inside of the cells before transforming to markdown via the pander package. Quick example:

> pander(data, split.cells = 30, split.table = Inf)

-------------------------------------------------------------------------
 Variable                      Label                      Classification 
---------- --------------------------------------------- ----------------
   VAR1                        LABEL                          Type1      

   VAR2                       A very                          Type2      
           loooooooooooooooooooooooooooooooooooooooooooo                 
              ooooooooooooooooooooooooooooooooooooooo                    
                    nnnnnnngggggggg label yall                           

   VAR3                        LAB3                           Type1      

   VAR4                        LAB4                           Type1      
-------------------------------------------------------------------------

Or if you will have several tables with the same problem, specify the split value once:

> panderOptions('table.split.table', Inf)
> pander(data)

-------------------------------------------------------------------------
 Variable                      Label                      Classification 
---------- --------------------------------------------- ----------------
   VAR1                        LABEL                          Type1      

   VAR2                       A very                          Type2      
           loooooooooooooooooooooooooooooooooooooooooooo                 
              ooooooooooooooooooooooooooooooooooooooo                    
                    nnnnnnngggggggg label yall                           

   VAR3                        LAB3                           Type1      

   VAR4                        LAB4                           Type1      
-------------------------------------------------------------------------

In short, look for the table.split.table and table.split.cells global options, although there are a bunch of other useful tweaks as well.