Dear all: This is one of those "should be easy" problems that I'm having great difficulty solving. I have a vector containing ID codes, and I need to generate a 3-column matrix that contains all possible combinations of three. For example, my ID vector looks like this: A B C D E I need to generate a matrix that looks like this: A B C A B D A B E A C B A C D A C E A D B A D C A D E .... and so on. (Yes, this could yield some very large matrices!) It's totally fine, though less desirable, if the resulting matrix contains combinations with "duplicates," e.g., A A A, A A B, or whatever. Thoughts? I'm pretty much stumped here. Thanks in advance for any help you can offer. Best regards, Brandon
Create unique sets of 3 from a vector of IDs?
6 messages · philozine, Dylan Beaudette, Kingsford Jones +1 more
On Tue, Dec 2, 2008 at 7:42 PM, philozine <philozine at yahoo.com> wrote:
Dear all: This is one of those "should be easy" problems that I'm having great difficulty solving. I have a vector containing ID codes, and I need to generate a 3-column matrix that contains all possible combinations of three. For example, my ID vector looks like this: A B C D E I need to generate a matrix that looks like this: A B C A B D A B E A C B A C D A C E A D B A D C A D E
Hi, Does this do what you want? expand.grid(letters[1:5], letters[1:5], letters[1:5]) D
.... and so on. (Yes, this could yield some very large matrices!) It's totally fine, though less desirable, if the resulting matrix contains combinations with "duplicates," e.g., A A A, A A B, or whatever. Thoughts? I'm pretty much stumped here. Thanks in advance for any help you can offer. Best regards, Brandon
______________________________________________ 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.
Dear Brandon, On Tue, Dec 2, 2008 at 10:46 PM, Dylan Beaudette
<dylan.beaudette at gmail.com> wrote:
On Tue, Dec 2, 2008 at 7:42 PM, philozine <philozine at yahoo.com> wrote:
Dear all: This is one of those "should be easy" problems that I'm having great difficulty solving. I have a vector containing ID codes, and I need to generate a 3-column matrix that contains all possible combinations of three. For example, my ID vector looks like this: A B C D E I need to generate a matrix that looks like this: A B C A B D A B E A C B A C D A C E A D B A D C A D E
Hi, Does this do what you want? expand.grid(letters[1:5], letters[1:5], letters[1:5]) D
Have a look at urnsamples() in the prob package. ID <- LETTERS[1:5] urnsamples(ID, size = 3, replace = FALSE, ordered = FALSE) Best, Jay *************************************************** G. Jay Kerns, Ph.D. Associate Professor Department of Mathematics & Statistics Youngstown State University Youngstown, OH 44555-0002 USA Office: 1035 Cushwa Hall Phone: (330) 941-3310 Office (voice mail) -3302 Department -3170 FAX E-mail: gkerns at ysu.edu http://www.cc.ysu.edu/~gjkerns/
However, I believe Brandon was trying to get the permutations of size 3, rather than combinations. Dylan provided a solution including repeats. Here's one without:
library(gtools) permutations(5, 3, LETTERS[1:5])
[,1] [,2] [,3] [1,] "A" "B" "C" [2,] "A" "B" "D" [3,] "A" "B" "E" [4,] "A" "C" "B" [5,] "A" "C" "D" [6,] "A" "C" "E" [7,] "A" "D" "B" [8,] "A" "D" "C" [9,] "A" "D" "E" [10,] "A" "E" "B" [11,] "A" "E" "C" [12,] "A" "E" "D" [13,] "B" "A" "C" [14,] "B" "A" "D" [15,] "B" "A" "E" [16,] "B" "C" "A" [17,] "B" "C" "D" [18,] "B" "C" "E" [19,] "B" "D" "A" [20,] "B" "D" "C" [21,] "B" "D" "E" [22,] "B" "E" "A" [23,] "B" "E" "C" [24,] "B" "E" "D" [25,] "C" "A" "B" [26,] "C" "A" "D" [27,] "C" "A" "E" [28,] "C" "B" "A" [29,] "C" "B" "D" [30,] "C" "B" "E" [31,] "C" "D" "A" [32,] "C" "D" "B" [33,] "C" "D" "E" [34,] "C" "E" "A" [35,] "C" "E" "B" [36,] "C" "E" "D" [37,] "D" "A" "B" [38,] "D" "A" "C" [39,] "D" "A" "E" [40,] "D" "B" "A" [41,] "D" "B" "C" [42,] "D" "B" "E" [43,] "D" "C" "A" [44,] "D" "C" "B" [45,] "D" "C" "E" [46,] "D" "E" "A" [47,] "D" "E" "B" [48,] "D" "E" "C" [49,] "E" "A" "B" [50,] "E" "A" "C" [51,] "E" "A" "D" [52,] "E" "B" "A" [53,] "E" "B" "C" [54,] "E" "B" "D" [55,] "E" "C" "A" [56,] "E" "C" "B" [57,] "E" "C" "D" [58,] "E" "D" "A" [59,] "E" "D" "B" [60,] "E" "D" "C" Kingsford Jones
On Tue, Dec 2, 2008 at 9:41 PM, G. Jay Kerns <gkerns at ysu.edu> wrote:
Dear Brandon, On Tue, Dec 2, 2008 at 10:46 PM, Dylan Beaudette <dylan.beaudette at gmail.com> wrote:
On Tue, Dec 2, 2008 at 7:42 PM, philozine <philozine at yahoo.com> wrote:
Dear all: This is one of those "should be easy" problems that I'm having great difficulty solving. I have a vector containing ID codes, and I need to generate a 3-column matrix that contains all possible combinations of three. For example, my ID vector looks like this: A B C D E I need to generate a matrix that looks like this: A B C A B D A B E A C B A C D A C E A D B A D C A D E
Hi, Does this do what you want? expand.grid(letters[1:5], letters[1:5], letters[1:5]) D
Have a look at urnsamples() in the prob package. ID <- LETTERS[1:5] urnsamples(ID, size = 3, replace = FALSE, ordered = FALSE) Best, Jay *************************************************** G. Jay Kerns, Ph.D. Associate Professor Department of Mathematics & Statistics Youngstown State University Youngstown, OH 44555-0002 USA Office: 1035 Cushwa Hall Phone: (330) 941-3310 Office (voice mail) -3302 Department -3170 FAX E-mail: gkerns at ysu.edu http://www.cc.ysu.edu/~gjkerns/
______________________________________________ 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.
Dear Kingsford, You are quite right, my mistake: urnsamples(ID, size = 3, replace = FALSE, ordered = TRUE) Thanks. Jay On Wed, Dec 3, 2008 at 12:04 AM, Kingsford Jones
<kingsfordjones at gmail.com> wrote:
However, I believe Brandon was trying to get the permutations of size 3, rather than combinations. Dylan provided a solution including repeats. Here's one without:
library(gtools) permutations(5, 3, LETTERS[1:5])
[,1] [,2] [,3] [1,] "A" "B" "C" [2,] "A" "B" "D" [3,] "A" "B" "E" [4,] "A" "C" "B" [5,] "A" "C" "D" [6,] "A" "C" "E" [7,] "A" "D" "B" [8,] "A" "D" "C" [9,] "A" "D" "E" [10,] "A" "E" "B" [11,] "A" "E" "C" [12,] "A" "E" "D" [13,] "B" "A" "C" [14,] "B" "A" "D" [15,] "B" "A" "E" [16,] "B" "C" "A" [17,] "B" "C" "D" [18,] "B" "C" "E" [19,] "B" "D" "A" [20,] "B" "D" "C" [21,] "B" "D" "E" [22,] "B" "E" "A" [23,] "B" "E" "C" [24,] "B" "E" "D" [25,] "C" "A" "B" [26,] "C" "A" "D" [27,] "C" "A" "E" [28,] "C" "B" "A" [29,] "C" "B" "D" [30,] "C" "B" "E" [31,] "C" "D" "A" [32,] "C" "D" "B" [33,] "C" "D" "E" [34,] "C" "E" "A" [35,] "C" "E" "B" [36,] "C" "E" "D" [37,] "D" "A" "B" [38,] "D" "A" "C" [39,] "D" "A" "E" [40,] "D" "B" "A" [41,] "D" "B" "C" [42,] "D" "B" "E" [43,] "D" "C" "A" [44,] "D" "C" "B" [45,] "D" "C" "E" [46,] "D" "E" "A" [47,] "D" "E" "B" [48,] "D" "E" "C" [49,] "E" "A" "B" [50,] "E" "A" "C" [51,] "E" "A" "D" [52,] "E" "B" "A" [53,] "E" "B" "C" [54,] "E" "B" "D" [55,] "E" "C" "A" [56,] "E" "C" "B" [57,] "E" "C" "D" [58,] "E" "D" "A" [59,] "E" "D" "B" [60,] "E" "D" "C" Kingsford Jones On Tue, Dec 2, 2008 at 9:41 PM, G. Jay Kerns <gkerns at ysu.edu> wrote:
Dear Brandon, On Tue, Dec 2, 2008 at 10:46 PM, Dylan Beaudette <dylan.beaudette at gmail.com> wrote:
On Tue, Dec 2, 2008 at 7:42 PM, philozine <philozine at yahoo.com> wrote:
Dear all: This is one of those "should be easy" problems that I'm having great difficulty solving. I have a vector containing ID codes, and I need to generate a 3-column matrix that contains all possible combinations of three. For example, my ID vector looks like this: A B C D E I need to generate a matrix that looks like this: A B C A B D A B E A C B A C D A C E A D B A D C A D E
Hi, Does this do what you want? expand.grid(letters[1:5], letters[1:5], letters[1:5]) D
Have a look at urnsamples() in the prob package. ID <- LETTERS[1:5] urnsamples(ID, size = 3, replace = FALSE, ordered = FALSE) Best, Jay *************************************************** G. Jay Kerns, Ph.D. Associate Professor Department of Mathematics & Statistics Youngstown State University Youngstown, OH 44555-0002 USA Office: 1035 Cushwa Hall Phone: (330) 941-3310 Office (voice mail) -3302 Department -3170 FAX E-mail: gkerns at ysu.edu http://www.cc.ysu.edu/~gjkerns/
______________________________________________ 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.
*************************************************** G. Jay Kerns, Ph.D. Associate Professor Department of Mathematics & Statistics Youngstown State University Youngstown, OH 44555-0002 USA Office: 1035 Cushwa Hall Phone: (330) 941-3310 Office (voice mail) -3302 Department -3170 FAX E-mail: gkerns at ysu.edu http://www.cc.ysu.edu/~gjkerns/
Dear all: These solutions work beautifully. Many, many thanks. And apologies for my lazy language! I did indeed mean permutations.... Best regards, Brandon
--- On Wed, 12/3/08, G. Jay Kerns <gkerns at ysu.edu> wrote:
From: G. Jay Kerns <gkerns at ysu.edu> Subject: Re: [R] Create unique sets of 3 from a vector of IDs? To: "Kingsford Jones" <kingsfordjones at gmail.com> Cc: r-help at r-project.org Date: Wednesday, December 3, 2008, 12:12 AM Dear Kingsford, You are quite right, my mistake: urnsamples(ID, size = 3, replace = FALSE, ordered = TRUE) Thanks. Jay On Wed, Dec 3, 2008 at 12:04 AM, Kingsford Jones <kingsfordjones at gmail.com> wrote:
However, I believe Brandon was trying to get the
permutations of size
3, rather than combinations. Dylan provided a
solution including
repeats. Here's one without:
library(gtools) permutations(5, 3, LETTERS[1:5])
[,1] [,2] [,3] [1,] "A" "B" "C" [2,] "A" "B" "D" [3,] "A" "B" "E" [4,] "A" "C" "B" [5,] "A" "C" "D" [6,] "A" "C" "E" [7,] "A" "D" "B" [8,] "A" "D" "C" [9,] "A" "D" "E" [10,] "A" "E" "B" [11,] "A" "E" "C" [12,] "A" "E" "D" [13,] "B" "A" "C" [14,] "B" "A" "D" [15,] "B" "A" "E" [16,] "B" "C" "A" [17,] "B" "C" "D" [18,] "B" "C" "E" [19,] "B" "D" "A" [20,] "B" "D" "C" [21,] "B" "D" "E" [22,] "B" "E" "A" [23,] "B" "E" "C" [24,] "B" "E" "D" [25,] "C" "A" "B" [26,] "C" "A" "D" [27,] "C" "A" "E" [28,] "C" "B" "A" [29,] "C" "B" "D" [30,] "C" "B" "E" [31,] "C" "D" "A" [32,] "C" "D" "B" [33,] "C" "D" "E" [34,] "C" "E" "A" [35,] "C" "E" "B" [36,] "C" "E" "D" [37,] "D" "A" "B" [38,] "D" "A" "C" [39,] "D" "A" "E" [40,] "D" "B" "A" [41,] "D" "B" "C" [42,] "D" "B" "E" [43,] "D" "C" "A" [44,] "D" "C" "B" [45,] "D" "C" "E" [46,] "D" "E" "A" [47,] "D" "E" "B" [48,] "D" "E" "C" [49,] "E" "A" "B" [50,] "E" "A" "C" [51,] "E" "A" "D" [52,] "E" "B" "A" [53,] "E" "B" "C" [54,] "E" "B" "D" [55,] "E" "C" "A" [56,] "E" "C" "B" [57,] "E" "C" "D" [58,] "E" "D" "A" [59,] "E" "D" "B" [60,] "E" "D" "C" Kingsford Jones On Tue, Dec 2, 2008 at 9:41 PM, G. Jay Kerns
<gkerns at ysu.edu> wrote:
Dear Brandon, On Tue, Dec 2, 2008 at 10:46 PM, Dylan Beaudette <dylan.beaudette at gmail.com> wrote:
On Tue, Dec 2, 2008 at 7:42 PM, philozine
<philozine at yahoo.com> wrote:
Dear all: This is one of those "should be
easy" problems that I'm having great difficulty solving. I have a vector containing ID codes, and I need to generate a 3-column matrix that contains all possible combinations of three.
For example, my ID vector looks like this: A B C D E I need to generate a matrix that looks
like this:
A B C A B D A B E A C B A C D A C E A D B A D C A D E
Hi, Does this do what you want? expand.grid(letters[1:5], letters[1:5],
letters[1:5])
D
Have a look at urnsamples() in the prob package. ID <- LETTERS[1:5] urnsamples(ID, size = 3, replace = FALSE, ordered
= FALSE)
Best, Jay
***************************************************
G. Jay Kerns, Ph.D. Associate Professor Department of Mathematics & Statistics Youngstown State University Youngstown, OH 44555-0002 USA Office: 1035 Cushwa Hall Phone: (330) 941-3310 Office (voice mail) -3302 Department -3170 FAX E-mail: gkerns at ysu.edu http://www.cc.ysu.edu/~gjkerns/
______________________________________________ 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. -- *************************************************** G. Jay Kerns, Ph.D. Associate Professor Department of Mathematics & Statistics Youngstown State University Youngstown, OH 44555-0002 USA Office: 1035 Cushwa Hall Phone: (330) 941-3310 Office (voice mail) -3302 Department -3170 FAX E-mail: gkerns at ysu.edu http://www.cc.ysu.edu/~gjkerns/ ______________________________________________ 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.