R shortcuts

These might come up in a variety of contexts, but I think it's nice to know that R has a few built-in constants to prevent someone from tediously creating a vector such as c("a", "b", "c" ...). You can use LETTERS or letters, depending on whether you want the capital or lower-case letters. There are also abbreviated and full month names, month.abb and mouth.name, which are very handy for making plots. And finally, there is pi.

I recently used LETTERS and letters to create different plotting symbols for each individual data point so I could easily identify which point is what. I had more than 62 (26 capital letters, 26 lower-case letters, and 10 digits), so I had to use some symbols as well. I'm not sure if there's a more elegant way to do this, but if anyone knows of any, I'd love to hear about it.