Suppose I have the following data frame (call it df):
Trt y1 y2 y3 y4
A1A 1 0 0 1
A1B 1 1 0 0
A1 C 0 1 0 1
A1D 1 1 1 1
What I want to do is concatenate columns y1 -> y4 into a contiguous
string (which I'll call df$conc), so that the final df looks like
Trt Conc
A1A 1001
A1B 1100
A1C 0101
A1D 1111
Now, if my initial dataframe was simply
1 0 0 1
1 1 0 0
0 1 0 1
1 1 1 1
then apply(df,1,paste,collapse="") does the trick, more or less.
But once I have a Trt column, this approach yields
A1A1001
A1B1100
A1C0101
A1D1111
I need to maintain the space between Trt, and the other columns. So, I'm
trying to concatenate a subset of columns in the data frame, but I don't
want to have to do something like create a cahracter vector of the
column names to do it (e.g.,
c("y1","y2","y3","y4"). Doing a few by
hand
that way is easy, but not if you have dozens to hundreds of columns to
work with.
Ideally, I'd like to be able to say
"concatenate df[,2:4], get rid of the spaces, pipe the concatenated
columns to a new named column, and drop the original columns from the
final df.
Heuristically,
df$conc <- concatenate df[,2:4] # making a new, 5th column in df
df[,2:4] <- NULL # to drop original columns 2 -> 4
Suggestions/pointers to the obvious appreciated.
Thanks in advance!
Hi Evan, How about this: df2<-data.frame(Trt=df[,1],Conc=apply(df[,2:5],1,paste,sep="",collapse="")) Jim On Fri, Mar 10, 2017 at 3:16 PM, Evan Cooch <evan.cooch at gmail.com> wrote:> Suppose I have the following data frame (call it df): > > Trt y1 y2 y3 y4 > A1A 1 0 0 1 > A1B 1 1 0 0 > A1 C 0 1 0 1 > A1D 1 1 1 1 > > What I want to do is concatenate columns y1 -> y4 into a contiguous string > (which I'll call df$conc), so that the final df looks like > > Trt Conc > A1A 1001 > A1B 1100 > A1C 0101 > A1D 1111 > > > Now, if my initial dataframe was simply > > 1 0 0 1 > 1 1 0 0 > 0 1 0 1 > 1 1 1 1 > > then apply(df,1,paste,collapse="") does the trick, more or less. > > But once I have a Trt column, this approach yields > > A1A1001 > A1B1100 > A1C0101 > A1D1111 > > I need to maintain the space between Trt, and the other columns. So, I'm > trying to concatenate a subset of columns in the data frame, but I don't > want to have to do something like create a cahracter vector of the column > names to do it (e.g., c("y1","y2","y3","y4"). Doing a few by hand that way > is easy, but not if you have dozens to hundreds of columns to work with. > > Ideally, I'd like to be able to say > > "concatenate df[,2:4], get rid of the spaces, pipe the concatenated columns > to a new named column, and drop the original columns from the final df. > > Heuristically, > > df$conc <- concatenate df[,2:4] # making a new, 5th column in df > df[,2:4] <- NULL # to drop original columns 2 -> 4 > > Suggestions/pointers to the obvious appreciated. > > Thanks in advance! > > ______________________________________________ > R-help at r-project.org 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.
I think you need to spend some time with an R tutorial or two, especially with regard to indexing. Unless I have misunderstood (apologies if I have), df$Conc <- apply(df[,-1],1,paste,collapse="") does it. -- Bert Bert Gunter "The trouble with having an open mind is that people keep coming along and sticking things into it." -- Opus (aka Berkeley Breathed in his "Bloom County" comic strip ) On Thu, Mar 9, 2017 at 8:16 PM, Evan Cooch <evan.cooch at gmail.com> wrote:> Suppose I have the following data frame (call it df): > > Trt y1 y2 y3 y4 > A1A 1 0 0 1 > A1B 1 1 0 0 > A1 C 0 1 0 1 > A1D 1 1 1 1 > > What I want to do is concatenate columns y1 -> y4 into a contiguous string > (which I'll call df$conc), so that the final df looks like > > Trt Conc > A1A 1001 > A1B 1100 > A1C 0101 > A1D 1111 > > > Now, if my initial dataframe was simply > > 1 0 0 1 > 1 1 0 0 > 0 1 0 1 > 1 1 1 1 > > then apply(df,1,paste,collapse="") does the trick, more or less. > > But once I have a Trt column, this approach yields > > A1A1001 > A1B1100 > A1C0101 > A1D1111 > > I need to maintain the space between Trt, and the other columns. So, I'm > trying to concatenate a subset of columns in the data frame, but I don't > want to have to do something like create a cahracter vector of the column > names to do it (e.g., c("y1","y2","y3","y4"). Doing a few by hand that way > is easy, but not if you have dozens to hundreds of columns to work with. > > Ideally, I'd like to be able to say > > "concatenate df[,2:4], get rid of the spaces, pipe the concatenated columns > to a new named column, and drop the original columns from the final df. > > Heuristically, > > df$conc <- concatenate df[,2:4] # making a new, 5th column in df > df[,2:4] <- NULL # to drop original columns 2 -> 4 > > Suggestions/pointers to the obvious appreciated. > > Thanks in advance! > > ______________________________________________ > R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code.
Hi Evan, the unite function of the tidyr package achieves the same as Jim suggested, but in perhaps a slightly more readable manner. Ulrik On Fri, 10 Mar 2017 at 07:50 Jim Lemon <drjimlemon at gmail.com> wrote:> Hi Evan, > How about this: > > df2<-data.frame(Trt=df[,1],Conc=apply(df[,2:5],1,paste,sep="",collapse="")) > > Jim > > On Fri, Mar 10, 2017 at 3:16 PM, Evan Cooch <evan.cooch at gmail.com> wrote: > > Suppose I have the following data frame (call it df): > > > > Trt y1 y2 y3 y4 > > A1A 1 0 0 1 > > A1B 1 1 0 0 > > A1 C 0 1 0 1 > > A1D 1 1 1 1 > > > > What I want to do is concatenate columns y1 -> y4 into a contiguous > string > > (which I'll call df$conc), so that the final df looks like > > > > Trt Conc > > A1A 1001 > > A1B 1100 > > A1C 0101 > > A1D 1111 > > > > > > Now, if my initial dataframe was simply > > > > 1 0 0 1 > > 1 1 0 0 > > 0 1 0 1 > > 1 1 1 1 > > > > then apply(df,1,paste,collapse="") does the trick, more or less. > > > > But once I have a Trt column, this approach yields > > > > A1A1001 > > A1B1100 > > A1C0101 > > A1D1111 > > > > I need to maintain the space between Trt, and the other columns. So, I'm > > trying to concatenate a subset of columns in the data frame, but I don't > > want to have to do something like create a cahracter vector of the column > > names to do it (e.g., c("y1","y2","y3","y4"). Doing a few by hand that > way > > is easy, but not if you have dozens to hundreds of columns to work with. > > > > Ideally, I'd like to be able to say > > > > "concatenate df[,2:4], get rid of the spaces, pipe the concatenated > columns > > to a new named column, and drop the original columns from the final df. > > > > Heuristically, > > > > df$conc <- concatenate df[,2:4] # making a new, 5th column in df > > df[,2:4] <- NULL # to drop original columns 2 -> 4 > > > > Suggestions/pointers to the obvious appreciated. > > > > Thanks in advance! > > > > ______________________________________________ > > R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see > > https://stat.ethz.ch/mailman/listinfo/r-help > > PLEASE do read the posting guide > http://www.R-project.org/posting-guide.html > > and provide commented, minimal, self-contained, reproducible code. > > ______________________________________________ > R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide > http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. >[[alternative HTML version deleted]]
On 3/10/2017 1:48 AM, Jim Lemon wrote:> Hi Evan, > How about this: > > df2<-data.frame(Trt=df[,1],Conc=apply(df[,2:5],1,paste,sep="",collapse="")) > > Jim > >Thanks!
On 3/10/2017 2:23 AM, Bert Gunter wrote:> I think you need to spend some time with an R tutorial or two, > especially with regard to indexing. > > Unless I have misunderstood (apologies if I have), > > df$Conc <- apply(df[,-1],1,paste,collapse="") > > does it. > > -- Bert > >\ Thanks -- sage advice.