[R] How to get the n (number of observations) per conditional group

Dax rienk.doetjes at gmail.com
Thu Aug 13 16:11:03 CEST 2009

Hello all,

I have a huge data set that I'm cleaning up a bit. I am extracted the
means per condition, but also need to get the n. Strangely enough I am
unable to find a function that could actually pull this off. I am
unable to use replications or count the rows using nrow.

What I am trying to obtain is the number of observations fitting
something along the lines of "data$total[data$spp==1&data$gyro==1&data

Can anyone help me?

More information about the R-help mailing list