Running totals
Glad it worked! The one "gotcha" is that it does not handle missing values, so for example:
cumsum(c(1, 2, 3, NA, 4))
[1] 1 3 6 NA NA both the NA, and everything after it become NA (missing). If you find yourself working with tables and frequencies and the like, you may also like (if you have not already seen): ?table # tabulate data ?function pulls up documentation ## example
table(c("john", "jane", "jane", "jane"))
jane john 3 1 ?xtabs # cross tabulation ## examples using the built in mtcars dataset ## (vs and am are 0/1 data)
xtabs( ~ vs + am, data = mtcars)
am vs 0 1 0 12 6 1 7 7 You may also like the vcd (visualizing categorical data) package by Michael Friendly: Keeping with the mtcars data, we might want to visualize that little cross tab: require(vcd) pairs(xtabs(~ vs + am, data = mtcars)) Cheers, Josh
On Mon, Nov 14, 2011 at 1:30 AM, Mark Carter <mcturra2000 at yahoo.co.uk> wrote:
From: Joshua Wiley <jwiley.psych at gmail.com>
dat$RTotal <- cumsum(dat$BAL)
Wow, that's really great. I'm starting to really enjoy using R. My statistical needs are not that great, but I love the way that R handles tabular data.
______________________________________________ R-help at r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
Joshua Wiley Ph.D. Student, Health Psychology Programmer Analyst II, ATS Statistical Consulting Group University of California, Los Angeles https://joshuawiley.com/