Sorting vector based on pairs of comparisons

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Sorting vector based on pairs of comparisons

 Dear All, This should be a quite established algorithm, but I have been searching for a couple days already without finding any satisfactory solution. I have a matrix defining pairs of Smaller-Larger arbitrary character values, like below Smaller <- c("ASD", "DFE", "ASD", "SDR", "EDF", "ASD") Larger <- c("SDR", "EDF", "KLM", "KLM", "SDR", "EDF" matComp <- cbind(Smaller, Larger) so that matComp looks like this       Smaller Larger [1,] "ASD"   "SDR" [2,] "DFE"   "EDF" [3,] "ASD"   "KLM" [4,] "SDR"   "KLM" [5,] "EDF"   "SDR" [6,] "ASD"   "EDF" This matrix establishes six pairs of "larger than" relationships that can be used to sort the unique values in the matrix,  > unique(as.vector(matComp)) [1] "ASD" "DFE" "SDR" "EDF" "KLM" Specifically, I would like to get this: sorted <- c("ASD", "DFE", "EDF", "SDR", "KLM") or, equally valid (my matrix does not have the full information): sorted <- c("DFE", "ASD", "EDF", "SDR", "KLM") Preferably, I would get the different combinations of the unique values that satisfy the "larger than" conditions in the matrix... I am sure this is a trivial problem, but I could not find any algorithm to solve it. Any help would be highly appreciated ______________________________________________ [hidden email] mailing list -- To UNSUBSCRIBE and more, see 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: Sorting vector based on pairs of comparisons

 Try this. Anything that appears only in Smaller is candidate for smallest. Among those, order is arbitrary. Anything that appears only in Larger is a candidate for largest. Among those order is arbitrary. Remove rows of matComp containing the already classified items.  Repeat with the smaller set. On Thu, Mar 14, 2019 at 07:30 Pedro Conte de Barros <[hidden email]> wrote: > Dear All, > > This should be a quite established algorithm, but I have been searching > for a couple days already without finding any satisfactory solution. > > I have a matrix defining pairs of Smaller-Larger arbitrary character > values, like below > > Smaller <- c("ASD", "DFE", "ASD", "SDR", "EDF", "ASD") > > Larger <- c("SDR", "EDF", "KLM", "KLM", "SDR", "EDF" > > matComp <- cbind(Smaller, Larger) > > so that matComp looks like this > >       Smaller Larger > [1,] "ASD"   "SDR" > [2,] "DFE"   "EDF" > [3,] "ASD"   "KLM" > [4,] "SDR"   "KLM" > [5,] "EDF"   "SDR" > [6,] "ASD"   "EDF" > > This matrix establishes six pairs of "larger than" relationships that > can be used to sort the unique values in the matrix, > >  > unique(as.vector(matComp)) > [1] "ASD" "DFE" "SDR" "EDF" "KLM" > > Specifically, I would like to get this: > > sorted <- c("ASD", "DFE", "EDF", "SDR", "KLM") > > or, equally valid (my matrix does not have the full information): > > sorted <- c("DFE", "ASD", "EDF", "SDR", "KLM") > > Preferably, I would get the different combinations of the unique values > that satisfy the "larger than" conditions in the matrix... > > > I am sure this is a trivial problem, but I could not find any algorithm > to solve it. > > Any help would be highly appreciated > > ______________________________________________ > [hidden email] mailing list -- To UNSUBSCRIBE and more, see > 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. >         [[alternative HTML version deleted]] ______________________________________________ [hidden email] mailing list -- To UNSUBSCRIBE and more, see 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: Sorting vector based on pairs of comparisons

 In reply to this post by Pedro Conte de Barros This cannot be done unless transitivity is guaranteed. Is it? S   L a  b b  c c  a Bert On Thu, Mar 14, 2019, 4:30 AM Pedro Conte de Barros <[hidden email]> wrote: > Dear All, > > This should be a quite established algorithm, but I have been searching > for a couple days already without finding any satisfactory solution. > > I have a matrix defining pairs of Smaller-Larger arbitrary character > values, like below > > Smaller <- c("ASD", "DFE", "ASD", "SDR", "EDF", "ASD") > > Larger <- c("SDR", "EDF", "KLM", "KLM", "SDR", "EDF" > > matComp <- cbind(Smaller, Larger) > > so that matComp looks like this > >       Smaller Larger > [1,] "ASD"   "SDR" > [2,] "DFE"   "EDF" > [3,] "ASD"   "KLM" > [4,] "SDR"   "KLM" > [5,] "EDF"   "SDR" > [6,] "ASD"   "EDF" > > This matrix establishes six pairs of "larger than" relationships that > can be used to sort the unique values in the matrix, > >  > unique(as.vector(matComp)) > [1] "ASD" "DFE" "SDR" "EDF" "KLM" > > Specifically, I would like to get this: > > sorted <- c("ASD", "DFE", "EDF", "SDR", "KLM") > > or, equally valid (my matrix does not have the full information): > > sorted <- c("DFE", "ASD", "EDF", "SDR", "KLM") > > Preferably, I would get the different combinations of the unique values > that satisfy the "larger than" conditions in the matrix... > > > I am sure this is a trivial problem, but I could not find any algorithm > to solve it. > > Any help would be highly appreciated > > ______________________________________________ > [hidden email] mailing list -- To UNSUBSCRIBE and more, see > 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. >         [[alternative HTML version deleted]] ______________________________________________ [hidden email] mailing list -- To UNSUBSCRIBE and more, see 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: Sorting vector based on pairs of comparisons

 Thanks for this. Yes, this is checked before trying to process this. Pedro On 14/03/2019 14.09, Bert Gunter wrote: This cannot be done unless transitivity is guaranteed. Is it? S   L a  b b  c c  a Bert On Thu, Mar 14, 2019, 4:30 AM Pedro Conte de Barros <[hidden email]> wrote: Dear All, This should be a quite established algorithm, but I have been searching for a couple days already without finding any satisfactory solution. I have a matrix defining pairs of Smaller-Larger arbitrary character values, like below Smaller <- c("ASD", "DFE", "ASD", "SDR", "EDF", "ASD") Larger <- c("SDR", "EDF", "KLM", "KLM", "SDR", "EDF" matComp <- cbind(Smaller, Larger) so that matComp looks like this       Smaller Larger [1,] "ASD"   "SDR" [2,] "DFE"   "EDF" [3,] "ASD"   "KLM" [4,] "SDR"   "KLM" [5,] "EDF"   "SDR" [6,] "ASD"   "EDF" This matrix establishes six pairs of "larger than" relationships that can be used to sort the unique values in the matrix,  > unique(as.vector(matComp)) [1] "ASD" "DFE" "SDR" "EDF" "KLM" Specifically, I would like to get this: sorted <- c("ASD", "DFE", "EDF", "SDR", "KLM") or, equally valid (my matrix does not have the full information): sorted <- c("DFE", "ASD", "EDF", "SDR", "KLM") Preferably, I would get the different combinations of the unique values that satisfy the "larger than" conditions in the matrix... I am sure this is a trivial problem, but I could not find any algorithm to solve it. Any help would be highly appreciated ______________________________________________ [hidden email] mailing list -- To UNSUBSCRIBE and more, see 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.         [[alternative HTML version deleted]] ______________________________________________ [hidden email] mailing list -- To UNSUBSCRIBE and more, see 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: Sorting vector based on pairs of comparisons

 In reply to this post by Pedro Conte de Barros This is called topological sorting in some circles.  The function below will give you one ordering that is consistent with the contraints but not all possible orderings.  I couldn't find such a function in core R so I wrote one a while back based on Kahn's algorithm, as described in Wikipedia. > Smaller <- c("ASD", "DFE", "ASD", "SDR", "EDF", "ASD") > Larger <- c("SDR", "EDF", "KLM", "KLM", "SDR", "EDF") > matComp <- cbind(Smaller, Larger) > sortTopologically(matComp, unique(as.vector(matComp))) [1] "ASD" "DFE" "EDF" "SDR" "KLM" Bill Dunlap TIBCO Software wdunlap tibco.com sortTopologically <- function(edgeMatrix, V) {     # edgeMatrix is 2-column matrix which describes a partial     #   ordering of a set of vertices. The first column is the 'from' vertex,     #   the second the 'to' vertex.     # V is the vector of all the vertices in the graph.     #     # Return a vector, L, consisting of the vertices in     #   V in an order consistent with the partial ordering     #   described by edgeMatrix.     # Throw an error if such an ordering is not possible.     #     # Use Kahn's algorithm ( https://en.wikipedia.org/wiki/Topological_sorting).     #     # Note that disconnected vertices will not be mentioned in edgeMatrix,     #   but will be in V.     stopifnot(is.matrix(edgeMatrix),               ncol(edgeMatrix)==2,               !any(is.na(edgeMatrix)),               !any(is.na(V)),               all(as.vector(edgeMatrix) %in% V))     L <- V[0] # match the type of the input     S <- setdiff(V, edgeMatrix[, 2])     V <- setdiff(V, S)     while(length(S) > 0) {         n <- S[1]         # cat("Adding", n, "to L", "\n")         L <- c(L, n)         S <- S[-1]         mRow <- edgeMatrix[,1] == n         edgeMatrix <- edgeMatrix[ !mRow, , drop=FALSE ]         S <- c(S, setdiff(V, edgeMatrix[,2]))         V <- setdiff(V, S)     }     if (nrow(edgeMatrix) > 0) {         stop("There are cycles in the dependency graph")     }     L } On Thu, Mar 14, 2019 at 4:30 AM Pedro Conte de Barros <[hidden email]> wrote: > Dear All, > > This should be a quite established algorithm, but I have been searching > for a couple days already without finding any satisfactory solution. > > I have a matrix defining pairs of Smaller-Larger arbitrary character > values, like below > > Smaller <- c("ASD", "DFE", "ASD", "SDR", "EDF", "ASD") > > Larger <- c("SDR", "EDF", "KLM", "KLM", "SDR", "EDF" > > matComp <- cbind(Smaller, Larger) > > so that matComp looks like this > >       Smaller Larger > [1,] "ASD"   "SDR" > [2,] "DFE"   "EDF" > [3,] "ASD"   "KLM" > [4,] "SDR"   "KLM" > [5,] "EDF"   "SDR" > [6,] "ASD"   "EDF" > > This matrix establishes six pairs of "larger than" relationships that > can be used to sort the unique values in the matrix, > >  > unique(as.vector(matComp)) > [1] "ASD" "DFE" "SDR" "EDF" "KLM" > > Specifically, I would like to get this: > > sorted <- c("ASD", "DFE", "EDF", "SDR", "KLM") > > or, equally valid (my matrix does not have the full information): > > sorted <- c("DFE", "ASD", "EDF", "SDR", "KLM") > > Preferably, I would get the different combinations of the unique values > that satisfy the "larger than" conditions in the matrix... > > > I am sure this is a trivial problem, but I could not find any algorithm > to solve it. > > Any help would be highly appreciated > > ______________________________________________ > [hidden email] mailing list -- To UNSUBSCRIBE and more, see > 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. >         [[alternative HTML version deleted]] ______________________________________________ [hidden email] mailing list -- To UNSUBSCRIBE and more, see 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: Sorting vector based on pairs of comparisons

 In reply to this post by Pedro Conte de Barros Hi Pedro, This looks too simple to me, but it seems to work: swap<-function(x,i1,i2) {  tmp<-x[i1]  x[i1]<-x[i2]  x[i2]<-tmp  return(x) } mpo<-function(x) {  L<-unique(as.vector(x))  for(i in 1:nrow(x)) {   i1<-which(L==x[i,1])   i2<-which(L==x[i,2])   if(i2 wrote: > > Dear All, > > This should be a quite established algorithm, but I have been searching > for a couple days already without finding any satisfactory solution. > > I have a matrix defining pairs of Smaller-Larger arbitrary character > values, like below > > Smaller <- c("ASD", "DFE", "ASD", "SDR", "EDF", "ASD") > > Larger <- c("SDR", "EDF", "KLM", "KLM", "SDR", "EDF" > > matComp <- cbind(Smaller, Larger) > > so that matComp looks like this > >       Smaller Larger > [1,] "ASD"   "SDR" > [2,] "DFE"   "EDF" > [3,] "ASD"   "KLM" > [4,] "SDR"   "KLM" > [5,] "EDF"   "SDR" > [6,] "ASD"   "EDF" > > This matrix establishes six pairs of "larger than" relationships that > can be used to sort the unique values in the matrix, > >  > unique(as.vector(matComp)) > [1] "ASD" "DFE" "SDR" "EDF" "KLM" > > Specifically, I would like to get this: > > sorted <- c("ASD", "DFE", "EDF", "SDR", "KLM") > > or, equally valid (my matrix does not have the full information): > > sorted <- c("DFE", "ASD", "EDF", "SDR", "KLM") > > Preferably, I would get the different combinations of the unique values > that satisfy the "larger than" conditions in the matrix... > > > I am sure this is a trivial problem, but I could not find any algorithm > to solve it. > > Any help would be highly appreciated > > ______________________________________________ > [hidden email] mailing list -- To UNSUBSCRIBE and more, see > 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. ______________________________________________ [hidden email] mailing list -- To UNSUBSCRIBE and more, see 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: Sorting vector based on pairs of comparisons

 If I understand correctly, the answer is a topological sort. Here is an explanation https://davidurbina.blog/on-partial-order-total-order-and-the-topological-sort/This was found by a simple web search on "Convert partial ordering to total ordering" Btw.  Please use search engines before posting here. Bert On Thu, Mar 14, 2019, 10:50 PM Jim Lemon <[hidden email]> wrote: > Hi Pedro, > This looks too simple to me, but it seems to work: > > swap<-function(x,i1,i2) { >  tmp<-x[i1] >  x[i1]<-x[i2] >  x[i2]<-tmp >  return(x) > } > mpo<-function(x) { >  L<-unique(as.vector(x)) >  for(i in 1:nrow(x)) { >   i1<-which(L==x[i,1]) >   i2<-which(L==x[i,2]) >   if(i2  } >  return(L) > } > mpo(matComp) > > Jim > > On Thu, Mar 14, 2019 at 10:30 PM Pedro Conte de Barros <[hidden email]> > wrote: > > > > Dear All, > > > > This should be a quite established algorithm, but I have been searching > > for a couple days already without finding any satisfactory solution. > > > > I have a matrix defining pairs of Smaller-Larger arbitrary character > > values, like below > > > > Smaller <- c("ASD", "DFE", "ASD", "SDR", "EDF", "ASD") > > > > Larger <- c("SDR", "EDF", "KLM", "KLM", "SDR", "EDF" > > > > matComp <- cbind(Smaller, Larger) > > > > so that matComp looks like this > > > >       Smaller Larger > > [1,] "ASD"   "SDR" > > [2,] "DFE"   "EDF" > > [3,] "ASD"   "KLM" > > [4,] "SDR"   "KLM" > > [5,] "EDF"   "SDR" > > [6,] "ASD"   "EDF" > > > > This matrix establishes six pairs of "larger than" relationships that > > can be used to sort the unique values in the matrix, > > > >  > unique(as.vector(matComp)) > > [1] "ASD" "DFE" "SDR" "EDF" "KLM" > > > > Specifically, I would like to get this: > > > > sorted <- c("ASD", "DFE", "EDF", "SDR", "KLM") > > > > or, equally valid (my matrix does not have the full information): > > > > sorted <- c("DFE", "ASD", "EDF", "SDR", "KLM") > > > > Preferably, I would get the different combinations of the unique values > > that satisfy the "larger than" conditions in the matrix... > > > > > > I am sure this is a trivial problem, but I could not find any algorithm > > to solve it. > > > > Any help would be highly appreciated > > > > ______________________________________________ > > [hidden email] mailing list -- To UNSUBSCRIBE and more, see > > 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. > > ______________________________________________ > [hidden email] mailing list -- To UNSUBSCRIBE and more, see > 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. >         [[alternative HTML version deleted]] ______________________________________________ [hidden email] mailing list -- To UNSUBSCRIBE and more, see 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.