I really like R's stem function, it creates a stem-and-leaf plot right in the R console, no fancy graphics devices required! In a recent R-help post, Ralf Bierig presented a very nice ASCII scatterplot representing two densities. Unfortunately, I don't know of any R function that will generate this type of plot, but I will argue that they are very useful to quickly visualize data, and to present data in ASCII-only media, such as an R mailing list message.
I wrote a little prototype R function I am calling scat ( to compliment stem, and because the output may be somewhat 'crappy' ) to generate a simple ASCII scatterplot. I put the code on a wiki. Unfortunately, the spambots have forced me to disallow editing of the wiki :-(.
You can load the latest version of scat by downloading the file from the wiki, or the original from here scat.R, or within R with
> source("http://biostatmatt.com/R/scat.R")
Here are some examples (note: this doesn't work well unless you view the ASCII in a monospace font):
> data(co2) #Mauna Loa Atmospheric CO2 Concentration > scat(c(co2[1:75]), rows=10, cols=80) ____________________________________________________________________________________ | | | * | | * * *** | | * *** * * * * | | ** * * * * * * ** * | | * * * * * ** * * * | | * * * * * * * * * * | | ** * ** * * * * * ** | | * * * * ** * * ** | | * * * * | | ** ** | |____________________________________________________________________________________| > x <- sin(seq(0,2*pi,length.out=30)) > scat(x, cols=15, rows=8) ___________________ | | | * | | **** | | * * | | * * | | * ** * | | * * | | * * | | **** | |___________________| > library(MASS) > data(galaxies) #Velocities for 82 Galaxies > d <- density(galaxies) > scat(d$y, d$x) ______________________________________________________ | | | * | | ** | | **** | | * * | | * ** | | * *** | | * ** | | * * | | * * | | * * | | * * | | * * | | * * | | * * | | * ** | | * * | | *** ** ** | | ** ** * ** | | ** ** *** ** **** | | *** ******* ******** ******* | |______________________________________________________|