CODEWITHSUNDEEP
rstringpermutation
bud.dugong
bud.dugong

Reputation: 759

How to generate all string permutations with given sets of letters at each position in R

I am sure this has been asked and solved before, but probably I am searching for the wrong terms. I cannot find the relevant thread.

In R, I would like to generate all possible words / strings, where each position can take only a set of values, like

etc. Eg.: BABC is a solution but DABC is not.

If you can point me towards a solution, I would really appreciate!

Thanks for your time!

... timb!, timc!, timd! ...

thx, Bud

Upvotes: 0

Views: 80

Answers (3)

user12728748
user12728748

Reputation: 8506

expand.grid is your friend here.

A simple solution:

apply(expand.grid(list(
    LETTERS[1:3],
    LETTERS[1:4],
    LETTERS[1:3],
    LETTERS[2:4])), 1, paste, collapse = "")
#>   [1] "AAAB" "BAAB" "CAAB" "ABAB" "BBAB" "CBAB" "ACAB" "BCAB" "CCAB" "ADAB"
#>  [11] "BDAB" "CDAB" "AABB" "BABB" "CABB" "ABBB" "BBBB" "CBBB" "ACBB" "BCBB"
#>  [21] "CCBB" "ADBB" "BDBB" "CDBB" "AACB" "BACB" "CACB" "ABCB" "BBCB" "CBCB"
#>  [31] "ACCB" "BCCB" "CCCB" "ADCB" "BDCB" "CDCB" "AAAC" "BAAC" "CAAC" "ABAC"
#>  [41] "BBAC" "CBAC" "ACAC" "BCAC" "CCAC" "ADAC" "BDAC" "CDAC" "AABC" "BABC"
#>  [51] "CABC" "ABBC" "BBBC" "CBBC" "ACBC" "BCBC" "CCBC" "ADBC" "BDBC" "CDBC"
#>  [61] "AACC" "BACC" "CACC" "ABCC" "BBCC" "CBCC" "ACCC" "BCCC" "CCCC" "ADCC"
#>  [71] "BDCC" "CDCC" "AAAD" "BAAD" "CAAD" "ABAD" "BBAD" "CBAD" "ACAD" "BCAD"
#>  [81] "CCAD" "ADAD" "BDAD" "CDAD" "AABD" "BABD" "CABD" "ABBD" "BBBD" "CBBD"
#>  [91] "ACBD" "BCBD" "CCBD" "ADBD" "BDBD" "CDBD" "AACD" "BACD" "CACD" "ABCD"
#> [101] "BBCD" "CBCD" "ACCD" "BCCD" "CCCD" "ADCD" "BDCD" "CDCD"

Created on 2020-06-18 by the reprex package (v0.3.0)

Upvotes: 1

Daniel O
Daniel O

Reputation: 4358

In Base R we can do the following

pos1 <- c('A','B','C')
pos2 <- c('A','B','C','D')
pos4 <- c('B','C','D')

AllPos <- list(pos1,pos2,pos3,pos4)

result <- AllPos[1]

for(i in AllPos[-1] ){
    result <-  apply(merge(result ,i),1,paste0,collapse="")
}

> result 
  [1] "AAAB" "BAAB" "CAAB" "ABAB" "BBAB" "CBAB" "ACAB" "BCAB" "CCAB" "ADAB"
 [11] "BDAB" "CDAB" "AABB" "BABB" "CABB" "ABBB" "BBBB" "CBBB" "ACBB" "BCBB"
 [21] "CCBB" "ADBB" "BDBB" "CDBB" "AACB" "BACB" "CACB" "ABCB" "BBCB" "CBCB"
 [31] "ACCB" "BCCB" "CCCB" "ADCB" "BDCB" "CDCB" "AAAC" "BAAC" "CAAC" "ABAC"
 [41] "BBAC" "CBAC" "ACAC" "BCAC" "CCAC" "ADAC" "BDAC" "CDAC" "AABC" "BABC"
 [51] "CABC" "ABBC" "BBBC" "CBBC" "ACBC" "BCBC" "CCBC" "ADBC" "BDBC" "CDBC"
 [61] "AACC" "BACC" "CACC" "ABCC" "BBCC" "CBCC" "ACCC" "BCCC" "CCCC" "ADCC"
 [71] "BDCC" "CDCC" "AAAD" "BAAD" "CAAD" "ABAD" "BBAD" "CBAD" "ACAD" "BCAD"
 [81] "CCAD" "ADAD" "BDAD" "CDAD" "AABD" "BABD" "CABD" "ABBD" "BBBD" "CBBD"
 [91] "ACBD" "BCBD" "CCBD" "ADBD" "BDBD" "CDBD" "AACD" "BACD" "CACD" "ABCD"
[101] "BBCD" "CBCD" "ACCD" "BCCD" "CCCD" "ADCD" "BDCD" "CDCD"

Upvotes: 1

Allan Cameron
Allan Cameron

Reputation: 173803

A quick and dirty base R solution...

p1 <- "ABC"
p2 <- "ABCD"
p3 <- "ABC"
p4 <- "BCD"

apply(expand.grid(strsplit(p1, "")[[1]], strsplit(p2, "")[[1]],
            strsplit(p3, "")[[1]], strsplit(p4, "")[[1]]), 1, paste0, 
      collapse = "")
#>   [1] "AAAB" "BAAB" "CAAB" "ABAB" "BBAB" "CBAB" "ACAB" "BCAB" "CCAB" "ADAB"
#>  [11] "BDAB" "CDAB" "AABB" "BABB" "CABB" "ABBB" "BBBB" "CBBB" "ACBB" "BCBB"
#>  [21] "CCBB" "ADBB" "BDBB" "CDBB" "AACB" "BACB" "CACB" "ABCB" "BBCB" "CBCB"
#>  [31] "ACCB" "BCCB" "CCCB" "ADCB" "BDCB" "CDCB" "AAAC" "BAAC" "CAAC" "ABAC"
#>  [41] "BBAC" "CBAC" "ACAC" "BCAC" "CCAC" "ADAC" "BDAC" "CDAC" "AABC" "BABC"
#>  [51] "CABC" "ABBC" "BBBC" "CBBC" "ACBC" "BCBC" "CCBC" "ADBC" "BDBC" "CDBC"
#>  [61] "AACC" "BACC" "CACC" "ABCC" "BBCC" "CBCC" "ACCC" "BCCC" "CCCC" "ADCC"
#>  [71] "BDCC" "CDCC" "AAAD" "BAAD" "CAAD" "ABAD" "BBAD" "CBAD" "ACAD" "BCAD"
#>  [81] "CCAD" "ADAD" "BDAD" "CDAD" "AABD" "BABD" "CABD" "ABBD" "BBBD" "CBBD"
#>  [91] "ACBD" "BCBD" "CCBD" "ADBD" "BDBD" "CDBD" "AACD" "BACD" "CACD" "ABCD"
#> [101] "BBCD" "CBCD" "ACCD" "BCCD" "CCCD" "ADCD" "BDCD" "CDCD"

Created on 2020-06-18 by the reprex package (v0.3.0)

Upvotes: 1

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