## venerdì 26 giugno 2009

### Set the significant digits for each column in a xtable for fancy Sweave output

This tip may be useful in the situations when you need to set the number of digits to print for the different columns in a matrix/data.frame to be outputted as a LaTeX table.
For example:

```#install.packages("xtable") #library(xtable) tmp <- matrix(rnorm(9), 3, 3) xtmp <- xtable(tmp) digits(xtmp) <- c(0,0,3,4) print(xtmp, include.rownames = FALSE) # row names suppressed```

See here for a nice gallery depicting a large variety of outputs you can produce using the xtable package.

## venerdì 19 giugno 2009

### Iran Election analyzed with R

Here you can find a very interesting post depicting the R strengths in 'real-time statistics'.
I'd like to use the occasion to thank David Smith for hosting the best, imho, blog on R!

## lunedì 15 giugno 2009

### Replacing 0 with NA - an evergreen from the list

This thread from the R-help list describe an evergreen tip that, at least once, is proved useful in R practice.

## sabato 6 giugno 2009

### Two plot with a common legend - base graphics

If you need to share a common legend between two graphs using the ggplot2 package/paradigm take a look at this post from the Learning R blog.
The code below solves the same task using the R base graphics.

`png( "2plot1legend.png", width = 480, height = 680)par(mfrow = c(2, 1), oma = c(0, 0, 0, 2))plot(hp~mpg, data=mtcars, col=cyl,pch=19)plot(disp~wt, data=mtcars, col=cyl,pch=19)par(xpd=NA)#legend(locator(1), legend=as.numeric(levels(factor(mtcars\$cyl))), pch=19, col= as.numeric(levels(factor(mtcars\$cyl))) )legend(x=5.6, y=690, legend=as.numeric(levels(factor(mtcars\$cyl))), pch=19, col= as.numeric(levels(factor(mtcars\$cyl))) )dev.off()`