Thanks! On Sat, Jun 21, 2014 at 11:05 AM, Jorge I Velez <jorgeivanve...@gmail.com> wrote: > Hi Kate, > > You could try > > sum(X[, 1] == 1 & X[, 2] == 1) > > where X is your data set. > > HTH, > Jorge.- > > > > On Sun, Jun 22, 2014 at 12:57 AM, Kate Ignatius <kate.ignat...@gmail.com> > wrote: >> >> I have 4 columns, and about 300K plus rows with 0s and 1s. >> >> I'm trying to count how many rows satisfy a certain criteria... for >> instance, how many rows are there that have the first column == 1 as >> well as the second column == 1. >> >> I've tried using rowSums and colSums but it keeps giving me this type of >> error: >> >> Error in rowSums(X[1] == 1 & X[2] == 1) : >> 'x' must be an array of at least two dimensions >> >> Thanks in advance! >> >> ______________________________________________ >> R-help@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. > >
______________________________________________ R-help@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.
