Dear R people,
I have to deal with the output of a function which comes as a matrix of
vectors.
You can reproduce the structure as given below:
x <- list(c(1,2,4),c(1,3,5),c(0,1,0),
c(1,3,6,5),c(3,4,4,4),c(0,1,0,1),
c(3,7),c(1,2),c(0,1))
data <- matrix(x,byrow=TRUE,nrow=3)
colnames(data) <- c("First", "Length", "Value")
rownames(data) <- c("Case1", "Case2", "Case3")
> data
First Length Value
Case1 Numeric,3 Numeric,3 Numeric,3
Case2 Numeric,4 Numeric,4 Numeric,4
Case3 Numeric,2 Numeric,2 Numeric,2
> data["Case1",]
$First
[1] 1 2 4
$Length
[1] 1 3 5
$Value
[1] 0 1 0
--------------------
My goal now is to break the three vectors of each row of the matrix into
their elements, assigning each element to a certain "Sequence" (which
I
want to be numbered according to the position of the corresponding
values within the vectors), reshaping the whole as a data frame like this:
Case Sequence First Length Value
Case1 1 1 1 0
Case1 2 2 3 1
Case1 3 4 5 0
Case2 1 1 3 0
Case2 2 3 4 1
Case2 3 6 4 0
Case2 4 5 4 1
Case3 1 3 1 0
Case3 2 7 2 1
I suspect that there might be an elegant and not too complicated way to
do this with one or several of the functions provided by the 'reshape'
package, but due to my lack of experience with R in general, this
package in particular and the complexity of the task I wasn't able to
figure out how to do it so far.
Every hint or helpful comment is much appreciated!
Oliver
On Jan 31, 2010, at 9:53 AM, Oliver Gondring wrote:> Dear R people, > > I have to deal with the output of a function which comes as a matrix > of vectors.If that is so, then the object below does not represent it, because that is a matrix of _lists_.> You can reproduce the structure as given below: > > x <- list(c(1,2,4),c(1,3,5),c(0,1,0), > c(1,3,6,5),c(3,4,4,4),c(0,1,0,1), > c(3,7),c(1,2),c(0,1)) > data <- matrix(x,byrow=TRUE,nrow=3) > colnames(data) <- c("First", "Length", "Value") > rownames(data) <- c("Case1", "Case2", "Case3") > > > data > First Length Value > Case1 Numeric,3 Numeric,3 Numeric,3 > Case2 Numeric,4 Numeric,4 Numeric,4 > Case3 Numeric,2 Numeric,2 Numeric,2 > > > data["Case1",] > $First > [1] 1 2 4 > > $Length > [1] 1 3 5 > > $Value > [1] 0 1 0 > -------------------- > > My goal now is to break the three vectors of each row of the matrix > into their elements, assigning each element to a certain > "Sequence" (which I want to be numbered according to the position of > the corresponding values within the vectors), reshaping the whole as > a data frame like this:This is close to what you specify: > apply(data, 1, function(.x) cbind(1:length(.x$First), sapply(.x, function(.y) return(.y ) ) ) ) $Case1 First Length Value [1,] 1 1 1 0 [2,] 2 2 3 1 [3,] 3 4 5 0 $Case2 First Length Value [1,] 1 1 3 0 [2,] 2 3 4 1 [3,] 3 6 4 0 [4,] 4 5 4 1 $Case3 First Length Value [1,] 1 3 1 0 [2,] 2 7 2 1 And if you do.call(rbind, on the result you would get a matrix but loose the case labeling. Adding the Case labels proved to be a bit of a challenge to me. Maybe one of the wizards will take pity on us: > sapply(rownames(data), function(.x) cbind(.x, # those were the rownames cbind(1:length(data[.x, "First"][[1]]), # and that was the incremental counter sapply(data[.x, ], #and finally the values which unfortunately get turned into characters function(.y) return(.y ) ) ) ) ) $Case1 .x First Length Value [1,] "Case1" "1" "1" "1" "0" [2,] "Case1" "2" "2" "3" "1" [3,] "Case1" "3" "4" "5" "0" $Case2 .x First Length Value [1,] "Case2" "1" "1" "3" "0" [2,] "Case2" "2" "3" "4" "1" [3,] "Case2" "3" "6" "4" "0" [4,] "Case2" "4" "5" "4" "1" $Case3 .x First Length Value [1,] "Case3" "1" "3" "1" "0" [2,] "Case3" "2" "7" "2" "1" (I tried a couple of plyr efforts but that is not a package that I have had much success with.) -- David.> > Case Sequence First Length Value > > Case1 1 1 1 0 > Case1 2 2 3 1 > Case1 3 4 5 0 > > Case2 1 1 3 0 > Case2 2 3 4 1 > Case2 3 6 4 0 > Case2 4 5 4 1 > > Case3 1 3 1 0 > Case3 2 7 2 1 > > I suspect that there might be an elegant and not too complicated way > to do this with one or several of the functions provided by the > 'reshape' package, but due to my lack of experience with R in > general, this package in particular and the complexity of the task I > wasn't able to figure out how to do it so far. > > Every hint or helpful comment is much appreciated! > > Oliver > > ______________________________________________ > 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.David Winsemius, MD Heritage Laboratories West Hartford, CT
> -----Original Message----- > From: r-help-bounces at r-project.org > [mailto:r-help-bounces at r-project.org] On Behalf Of Oliver Gondring > Sent: Sunday, January 31, 2010 6:53 AM > To: r-help at r-project.org > Subject: [R] Reshaping matrix of vectors as dataframe > > Dear R people, > > I have to deal with the output of a function which comes as a > matrix of > vectors. > You can reproduce the structure as given below: > > x <- list(c(1,2,4),c(1,3,5),c(0,1,0), > c(1,3,6,5),c(3,4,4,4),c(0,1,0,1), > c(3,7),c(1,2),c(0,1)) > data <- matrix(x,byrow=TRUE,nrow=3) > colnames(data) <- c("First", "Length", "Value") > rownames(data) <- c("Case1", "Case2", "Case3") > > > data > First Length Value > Case1 Numeric,3 Numeric,3 Numeric,3 > Case2 Numeric,4 Numeric,4 Numeric,4 > Case3 Numeric,2 Numeric,2 Numeric,2 > > > data["Case1",] > $First > [1] 1 2 4 > > $Length > [1] 1 3 5 > > $Value > [1] 0 1 0 > -------------------- > > My goal now is to break the three vectors of each row of the > matrix into > their elements, assigning each element to a certain > "Sequence" (which I > want to be numbered according to the position of the corresponding > values within the vectors), reshaping the whole as a data > frame like this: > > Case Sequence First Length Value > > Case1 1 1 1 0 > Case1 2 2 3 1 > Case1 3 4 5 0 > > Case2 1 1 3 0 > Case2 2 3 4 1 > Case2 3 6 4 0 > Case2 4 5 4 1 > > Case3 1 3 1 0 > Case3 2 7 2 1The following is not terribly elegant, but is pretty easy to understand. > lengths<-sapply(data[,1],length) > data.frame(Case=rep(rownames(data),lengths), + Sequence=sequence(lengths), + apply(data,2,unlist), + row.names=NULL) Case Sequence First Length Value 1 Case1 1 1 1 0 2 Case1 2 2 3 1 3 Case1 3 4 5 0 4 Case2 1 1 3 0 5 Case2 2 3 4 1 6 Case2 3 6 4 0 7 Case2 4 5 4 1 8 Case3 1 3 1 0 9 Case3 2 7 2 1 It assumes that sapply(data[,k],length) is the same for all k in 1:ncol(data). If you do this often put it into a function that makes that check. It uses the much-maligned (by me) apply() function so it wastes effort "simplifying" the results of unlist into the columns of a matrix that data.frame() will immediately pull apart into columns. The following avoids apply() but is wordier > data.frame(Case=rep(rownames(data),lengths), + Sequence=sequence(lengths), + lapply(split(data,colnames(data)[col(data)]), unlist), + row.names=NULL) Case Sequence First Length Value 1 Case1 1 1 1 0 2 Case1 2 2 3 1 3 Case1 3 4 5 0 4 Case2 1 1 3 0 5 Case2 2 3 4 1 6 Case2 3 6 4 0 7 Case2 4 5 4 1 8 Case3 1 3 1 0 9 Case3 2 7 2 1 Bill Dunlap Spotfire, TIBCO Software wdunlap tibco.com> > I suspect that there might be an elegant and not too > complicated way to > do this with one or several of the functions provided by the > 'reshape' > package, but due to my lack of experience with R in general, this > package in particular and the complexity of the task I wasn't able to > figure out how to do it so far. > > Every hint or helpful comment is much appreciated! > > Oliver > > ______________________________________________ > 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. >