Still it is pretty slow when entering values into a large matrix. Case in point:
> a <- matrix(nrow=10000,ncol=10000) > system.time(a[1,1] <- 1903908.80385) user system elapsed 30.840 6.226 41.416 > is.matrix(a) [1] TRUE Is there a better way to enter values into large matrices? If I have to spend 41 secs each time I enter into a cell and I have 10000x10000 cells to enter that is impractical! --Nnamdi Rolf Turner-3 wrote: > > > On 17/04/2008, at 9:33 AM, Charles C. Berry wrote: > > <snip> > >> I'll lay odds that Matthew's 'matrix' is actually a data.frame, and >> I'll not be surprised if the columns are factors. > > <snip> > > I suspect that you're right. > > ***Why*** can't people distinguish between data frames and matrices? > If they were the same <expletive deleted> thing, there wouldn't be two > different terms for them, would there? > > cheers, > > Rolf Turner > > ###################################################################### > Attention:\ This e-mail message is privileged and confid...{{dropped:9}} > > ______________________________________________ > 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. > > -- View this message in context: http://www.nabble.com/efficiently-replacing-values-in-a-matrix-tp16732795p16763578.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ 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.