but in perhaps a slightly more readable manner.

> 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 <

[hidden email]> 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!

> >

> > ______________________________________________

> >

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> >

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.

>