Hi, how can I produce random data which lies around a straight line with angle 45 degree. Similar to this image: http://zoonek2.free.fr/UNIX/48_R/g134.png Cheers -- View this message in context: http://old.nabble.com/Random-data-tp26513822p26513822.html Sent from the R help mailing list archive at Nabble.com.
That's not a 45-degree angle: the x and y scales are quite different. But you can use corgen from the ecodist package to create correlated x and y variables, and then adjust the scale as needed. Sarah On Wed, Nov 25, 2009 at 9:42 AM, mentor_ <mentor_ at gmx.net> wrote:> > Hi, > > how can I produce random data which lies around a straight line with angle > 45 degree. > Similar to this image: http://zoonek2.free.fr/UNIX/48_R/g134.png > > Cheers-- Sarah Goslee http://www.functionaldiversity.org
one way is: x <- sort(rnorm(100)) y <- rnorm(100, mean = x, sd = 0.3) plot(x, y) abline(a = 0, b = 1) I hope it helps. Best, Dimitris mentor_ wrote:> Hi, > > how can I produce random data which lies around a straight line with angle > 45 degree. > Similar to this image: http://zoonek2.free.fr/UNIX/48_R/g134.png > > Cheers-- Dimitris Rizopoulos Assistant Professor Department of Biostatistics Erasmus University Medical Center Address: PO Box 2040, 3000 CA Rotterdam, the Netherlands Tel: +31/(0)10/7043478 Fax: +31/(0)10/7043014
One option, first, generate the range of "x" data that you want, then add normally distributed noise to each x, these will be your "y" data. n <- 20 x <- sample(20:50, n) y <- rnorm(n, mean = x, sd = 3) plot(y ~ x) Erik> -----Original Message----- > From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-project.org] > On Behalf Of mentor_ > Sent: Wednesday, November 25, 2009 8:43 AM > To: r-help at r-project.org > Subject: [R] Random data > > > Hi, > > how can I produce random data which lies around a straight line with angle > 45 degree. > Similar to this image: http://zoonek2.free.fr/UNIX/48_R/g134.png > > Cheers > -- > View this message in context: http://old.nabble.com/Random-data- > tp26513822p26513822.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > 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.