# Combination with repetition

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## Combination with repetition

 Hi there! I can't find any information about creating combinations with repetitions in R. The function combn() does create combinations, but _without_ repetitions.     Here is what I need to do: svIter <- 1000 xx <- matrix(rnorm(m*n), c(m, n)) sequence <- seq(range(xx)[1], range(xx)[2], length.out = svIter^(1/q)) expand.grid(secuence, secuence, .../q times/..., secuence) That is, I need a grid which covers a q-dimensional space with range range(xx) for each dimension, and a total number of points close to svIter. My problem could be solved by writting the expand.grid call at runtime, but I think that is not very elegant and, overall, I don't know how to do that. If combn() accepted repetitions, it'd be solved also.     Any help will be greatly appreciated.     Bests, --                                                      -- Jose Luis Aznarte M.       http://decsai.ugr.es/~jlaznarteDepartment of Computer Science and Artificial Intelligence Universidad de Granada           Tel. +34 - 958 - 24 04 67 GRANADA (Spain)                  Fax: +34 - 958 - 24 00 79 ______________________________________________ [hidden email] mailing list https://stat.ethz.ch/mailman/listinfo/r-helpPLEASE do read the posting guide http://www.R-project.org/posting-guide.htmland provide commented, minimal, self-contained, reproducible code.
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## Re: Combination with repetition

 you could use something like the following: expand.grid(rep(list(1:3), 4)) I hope it helps. Best, Dimitris Jose Luis Aznarte M. wrote: >   Hi there! I can't find any information about creating combinations > with repetitions in R. The function combn() does create combinations, > but _without_ repetitions. >    Here is what I need to do: > > svIter <- 1000 > xx <- matrix(rnorm(m*n), c(m, n)) > sequence <- seq(range(xx)[1], range(xx)[2], length.out = svIter^(1/q)) > expand.grid(secuence, secuence, .../q times/..., secuence) > > That is, I need a grid which covers a q-dimensional space with range > range(xx) for each dimension, and a total number of points close to > svIter. My problem could be solved by writting the expand.grid call at > runtime, but I think that is not very elegant and, overall, I don't know > how to do that. If combn() accepted repetitions, it'd be solved also. >    Any help will be greatly appreciated. >    Bests, > > --                                                      -- > Jose Luis Aznarte M.       http://decsai.ugr.es/~jlaznarte> Department of Computer Science and Artificial Intelligence > Universidad de Granada           Tel. +34 - 958 - 24 04 67 > GRANADA (Spain)                  Fax: +34 - 958 - 24 00 79 > > ______________________________________________ > [hidden email] 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. > > -- Dimitris Rizopoulos Biostatistical Centre School of Public Health Catholic University of Leuven Address: Kapucijnenvoer 35, Leuven, Belgium Tel: +32/(0)16/336899 Fax: +32/(0)16/337015 Web: http://perswww.kuleuven.be/dimitris_rizopoulos/Disclaimer: http://www.kuleuven.be/cwis/email_disclaimer.htm______________________________________________ [hidden email] mailing list https://stat.ethz.ch/mailman/listinfo/r-helpPLEASE do read the posting guide http://www.R-project.org/posting-guide.htmland provide commented, minimal, self-contained, reproducible code.
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## Re: Combination with repetition

 In reply to this post by "José Luis Aznarte M."-2 On Fri, 15 Aug 2008, Jose Luis Aznarte M. wrote: >  Hi there! I can't find any information about creating combinations with > repetitions in R. The function combn() does create combinations, but > _without_ repetitions. >    Here is what I need to do: > > svIter <- 1000 > xx <- matrix(rnorm(m*n), c(m, n)) > sequence <- seq(range(xx)[1], range(xx)[2], length.out = svIter^(1/q)) > expand.grid(secuence, secuence, .../q times/..., secuence) See   ?do.call do.call( expand.grid, rep( list(sequence), q ) ) HTH, Chuck p.s. Using function names as object names (e.g. 'q') is considered bad practice > > That is, I need a grid which covers a q-dimensional space with range > range(xx) for each dimension, and a total number of points close to svIter. > My problem could be solved by writting the expand.grid call at runtime, but I > think that is not very elegant and, overall, I don't know how to do that. If > combn() accepted repetitions, it'd be solved also. >    Any help will be greatly appreciated. >    Bests, > > --                                                      -- > Jose Luis Aznarte M.       http://decsai.ugr.es/~jlaznarte> Department of Computer Science and Artificial Intelligence > Universidad de Granada           Tel. +34 - 958 - 24 04 67 > GRANADA (Spain)                  Fax: +34 - 958 - 24 00 79 > > ______________________________________________ > [hidden email] 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. > Charles C. Berry                            (858) 534-2098                                              Dept of Family/Preventive Medicine E mailto:[hidden email]            UC San Diego http://famprevmed.ucsd.edu/faculty/cberry/  La Jolla, San Diego 92093-0901 ______________________________________________ [hidden email] mailing list https://stat.ethz.ch/mailman/listinfo/r-helpPLEASE do read the posting guide http://www.R-project.org/posting-guide.htmland provide commented, minimal, self-contained, reproducible code.
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