[R] Custom LaTeX tables

[Gabor Grothendieck]

On Tue, Feb 26, 2008 at 10:58 AM, Werner Wernersen
<pensterfuzzer at yahoo.de> wrote:
> Hello,
>
> I am very happy that I have Sweave and R to write my
> papers. But I still have to do some tables by hand
> since I have not found out how I can customize the
> latex tables produced by R further (I mainly use
> xtable()). Like for instance, I have a table which
> needs an extra row every few rows as a group header
> and sometimes I want some extra horizontal lines in
> the table and also a multicolumn heading.
>
> How do you guys cope with such cases, do you set the
> table by hand in the end or have you found a neat way
> to deal with this?
>
> Many thanks and regards,
>  Werner

A few options are:

- Hmisc latex() supports multicolumn headings and group headings
although the large number of arguments may be daunting

- xtable (and Hmisc's latex too) supports a style of combining
latex fragments with the xtable.  The add.to.row= argument on
print.xtable is the
one to notice. e.g. using the builtin BOD data frame this adds a 2nd row
of headings and a group heading:

print(xtable(BOD, align = "r|r|r|"), include.rownames = FALSE,
    add.to.row = list(pos = list(0, 3),
        command = c("\\multicolumn{1}{|c|}{(days)} &
\\multicolumn{1}{|c|}{(mg/l)} \\\\ ",
        "\\hline \\multicolumn{2}{|l|}{Special Values} \\\\ \\hline ")))

- given the freedom from restrictions I find its often just best to
do it manually in latex or if you have many tables with the same format
in a report to generate a report-specific table layout wrapper that emits
the latex you need.