That is not what his 'for' loops are doing. He is iterating through all combinations and would have created 784. So his problem statement did not match the code that he sent.
On Thu, Jun 18, 2009 at 2:12 PM, Marc Schwartz <marc_schwa...@me.com> wrote: > Alexandre did say 28 datasets, not 784 (28 * 28).... > > Thus, either: > > mapply(rnorm, n = 500, mean = a1, sd = a2) > > or > > apply(cbind(a1, a2), 1, function(x) rnorm(500, x[1], x[2])) > > > HTH, > > Marc Schwartz > > On Jun 18, 2009, at 12:51 PM, Henrique Dallazuanna wrote: > > Try this also: >> >> a <- expand.grid(a1, a2) >> x <- mapply(rnorm, n = 500, mean = a[,1], sd = a[,2]) >> >> On Thu, Jun 18, 2009 at 2:10 PM, Alexandre Lockhart < >> alexandre_geor...@hotmail.com> wrote: >> >> >>> Hello: >>> >>> My problem is that I have a data frame of means, and a data frame of >>> standard deviations which match up to each mean. I have been trying to >>> create 500 random numbers in a given dataset for each mean/sd >>> combination, >>> but I am only able to generate the last value in each data set to create >>> one >>> dataset (there should be 28 in all). Examining my code, what can I >>> change >>> to generate 28 datasets based on respective mean and sds? >>> >>> >>> >>> a1<-c(178.07,178.28,178.08,177.74,177.04,178.17,177.58,57.71,59.6,60.92,59.48,59.32,61.59,59.94,28.9,29.82,30.73,25.68,27.93,28.98,29.76,123.48,127.27,127.8,127.2,127.13,126.71,125.5) >>> >>> >>> a2<-c(1.69,1.3,1,.18,1.53,1.31,1.35,1.83,1.56,1.12,.74,1.48,1.67,1.53,.95,.87,0.03,1.12,1.95,1.22,1.04,1.64,1.83,1,1,1.08,1.35,2.37) >>> for(i in 1:length(a1)) >>> for(j in 1:length(a2)) >>> x<-rnorm(500,mean=a1[i],sd=a2[j]) >>> >>> Thank you, >>> >>> Agl >>> >> > ______________________________________________ > 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<http://www.r-project.org/posting-guide.html> > and provide commented, minimal, self-contained, reproducible code. > -- Jim Holtman Cincinnati, OH +1 513 646 9390 What is the problem that you are trying to solve? [[alternative HTML version deleted]] ______________________________________________ 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.
