[R] query on xtable output

[ManuelPerera-Chang@fmc-ag.com]

Dear all,
I am exporting to latex a matrix via xtable. My matrix includes e.g. 4 rows
and 4 columns. The first two rows containing real values(e.g. a laboratory
parameter's mean value), and the two rows at the bottom containing only
integers (number of cases).

>
mymat<-matrix(c(c(10.52,2.52,12.35,3.63),c(3.52,16.25,13.62,6.36),c(11,12,15,16),c(14,15,16,18)),4,4,byrow=TRUE)
> mymat
      [,1]  [,2]  [,3]  [,4]
[1,] 10.52  2.52 12.35  3.63
[2,]  3.52  6.25  3.62  6.36
[3,] 11.00 12.00 15.00 16.00
[4,] 14.00 15.00 16.00 18.00

>
trend_table<-xtable(mymat,caption="Caption",display=c('s','fg','fg','fg','fg'),size='small')

The R help on xtable states that "fg" displays 'digits' as number of
_significant_ digits. As a result no decimal places are shown in the last
two rows, as I wanted, but no decimal places are shown neither in the first
two rows, if the real value in the cell is greater than 10, and only 1
decimal place if the value in the cell is lower than 10.

Thus I got the following Latex output: ...

> trend_table

\begin{table}[ht]
\begin{center}
\begin{tabular}{rrrrr}
\hline
 & 1 & 2 & 3 & 4 \\
\hline
1 &  11 & 2.5 &  12 & 3.6 \\  I would like to have more decimal places here
e.g. 10.5 or 10.52 instead of 11.
2 & 3.5 &  16 &  14 & 6.4 \\
3 &  11 &  12 &  15 &  16 \\ This is what I expect, no commas and decimal
0-s for the number of cases.
4 &  14 &  15 &  16 &  18 \\
\hline
\end{tabular}
\caption{Caption}
\end{center}
\end{table}

 I would prefer to show 1 additional decimal  in both cases.

Thus my question is how to modify the setting for _significant_ digits(in
xtable??) in order to print the correctly formated values.

Sorry for reposting my question, ...

Thank you

Manuel