xtable + knitr set column width html - html

Question

How can I set the column widths of individual columns in the knitr (Rmd) output of a code chunk using the xtable package?
MWE
```{r setup, include=FALSE}
library(xtable)
```
```{r, results="asis", echo=FALSE}
print(xtable(mtcars[1:2, 1:2]), type="html", include.rownames=FALSE)
```
Lets say I want to make column_#1 - 2 inches wide and column_#2 - 3 inches wide.
I'm not married to xtable here but don't know of any other html table out packages that could do this.

Answer 1

You can change the css used by xtable to format the table and change columns width. It does not allow changing individual columns though.
See http://nsaunders.wordpress.com/2012/08/27/custom-css-for-html-generated-using-rstudio/
An example below:
Add a stylesheet (here named custom.css) to the same folder as your markdown file.
table {
max-width: 95%;
border: 1px solid #ccc;
}
th {
background-color: #000000;
color: #ffffff;
width: 100px;
}
td {
background-color: #dcdcdc;
width: 100px;
}
and set the options to use this stylesheet
```{r setup, include=FALSE}
library(xtable)
options(rstudio.markdownToHTML =
function(inputFile, outputFile) {
require(markdown)
markdownToHTML(inputFile, outputFile, stylesheet='custom.css')
}
)
```
```{r, results="asis", echo=FALSE}
print(xtable(mtcars[1:2, 1:2]), type="html", include.rownames=FALSE)
```
It might be possible to hack the print.xtable function to get more flexibility.