Hello, I was just wondering whether there is a quick way to divide a vector of data into four groups defined by the quantiles? i.e. 0-25% 25-50% 50-75% 75-100% Many thanks Dan -- ************************************************************** Daniel Brewer, Ph.D. Institute of Cancer Research Molecular Carcinogenesis Email: daniel.brewer at icr.ac.uk ************************************************************** The Institute of Cancer Research: Royal Cancer Hospital, a charitable Company Limited by Guarantee, Registered in England under Company No. 534147 with its Registered Office at 123 Old Brompton Road, London SW7 3RP. This e-mail message is confidential and for use by the a...{{dropped:2}}
check at cut() and split(), e.g., x <- rnorm(100) qx <- quantile(x) ind <- cut(x, qx, include.lowest = TRUE) split(x, ind) I hope it helps. Best, Dimitris Daniel Brewer wrote:> Hello, > > I was just wondering whether there is a quick way to divide a vector of > data into four groups defined by the quantiles? > i.e. > 0-25% > 25-50% > 50-75% > 75-100% > > Many thanks > > Dan >-- Dimitris Rizopoulos Assistant Professor Department of Biostatistics Erasmus Medical Center Address: PO Box 2040, 3000 CA Rotterdam, the Netherlands Tel: +31/(0)10/7043478 Fax: +31/(0)10/7043014
Daniel Brewer wrote:> Hello, > > I was just wondering whether there is a quick way to divide a vector of > data into four groups defined by the quantiles? > i.e. > 0-25% > 25-50% > 50-75% > 75-100% > > Many thanks > > Dan >library(Hmisc) cut2(x, g=4) -- Frank E Harrell Jr Professor and Chair School of Medicine Department of Biostatistics Vanderbilt University
The gtools package has quantcut. On Tue, Nov 18, 2008 at 6:53 AM, Daniel Brewer <daniel.brewer at icr.ac.uk> wrote:> Hello, > > I was just wondering whether there is a quick way to divide a vector of > data into four groups defined by the quantiles? > i.e. > 0-25% > 25-50% > 50-75% > 75-100% > > Many thanks > > Dan > > -- > ************************************************************** > Daniel Brewer, Ph.D. > > Institute of Cancer Research > Molecular Carcinogenesis > Email: daniel.brewer at icr.ac.uk > ************************************************************** > > The Institute of Cancer Research: Royal Cancer Hospital, a charitable Company Limited by Guarantee, Registered in England under Company No. 534147 with its Registered Office at 123 Old Brompton Road, London SW7 3RP. > > This e-mail message is confidential and for use by the a...{{dropped:2}} > > ______________________________________________ > 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. >