R help - Feb 2010 - split strings in a vector and convert it to a data.frame

hi,

I have a vector full of strings like;


xy_100_ab	xy_101_ab	xy_102_ab	xy_103_ab


I want to seperate each string in three pieces and the separator should be the
"_"

at the end I want a data.frame like:

column1 column2 column3
xy		100			ab
xy		101			ab
xy		102			ab
xy		103			ab


I tried strsplit but I couldn't figure out how to convert the list I get
into a data.frame.

I just need a function like read.table. But it seems that read.table only can
handle files, not vectors...

Hi Martin,

Here is a sugestion:

string <- c("xy_100_ab",
"xy_101_ab","xy_102_ab","xy_103_ab")
out <- data.frame( do.call( rbind, strsplit( string, '_' ) ) )
names(out) <- paste('column',1:3,sep="")
out

HTH,
Jorge

On Tue, Feb 9, 2010 at 6:46 PM, Martin Batholdy <> wrote:
> hi,
>
> I have a vector full of strings like;
>
>
> xy_100_ab       xy_101_ab       xy_102_ab       xy_103_ab
>
>
> I want to seperate each string in three pieces and the separator should be
> the "_"
>
> at the end I want a data.frame like:
>
> column1 column2 column3
> xy              100                     ab
> xy              101                     ab
> xy              102                     ab
> xy              103                     ab
>
>
> I tried strsplit but I couldn't figure out how to convert the list I
get
> into a data.frame.
>
> I just need a function like read.table. But it seems that read.table only
> can handle files, not vectors...
> ______________________________________________
> R-help@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.
>
	[[alternative HTML version deleted]]

On Feb 9, 2010, at 6:46 PM, Martin Batholdy wrote:
> hi,
>
> I have a vector full of strings like;
>
>
> xy_100_ab	xy_101_ab	xy_102_ab	xy_103_ab
>
>
> I want to seperate each string in three pieces and the separator  
> should be the "_"
>
> at the end I want a data.frame like:
>
> column1 column2 column3
> xy		100			ab
> xy		101			ab
> xy		102			ab
> xy		103			ab
>
There are probably easier ways but this works:

 > as.data.frame( t(sapply(1:4, function(x) strsplit(vec,
"_")[[x]])) )
   V1  V2 V3
1 xy 100 ab
2 xy 101 ab
3 xy 102 ab
4 xy 103 ab

I needed to transpose the matrix that resulted from the "sideways  
presentation" of the data.
>
> I tried strsplit but I couldn't figure out how to convert the list I  
> get into a data.frame.
>
> I just need a function like read.table. But it seems that read.table  
> only can handle files, not vectors...
> ______________________________________________
> 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

On Tue, Feb 9, 2010 at 6:46 PM, Martin Batholdy <batholdy at
googlemail.com> wrote:
> hi,
>
> I have a vector full of strings like;
>
>
> xy_100_ab ? ? ? xy_101_ab ? ? ? xy_102_ab ? ? ? xy_103_ab
>
>
> I want to seperate each string in three pieces and the separator should be
the "_"
>
> at the end I want a data.frame like:
>
> column1 column2 column3
> xy ? ? ? ? ? ? ?100 ? ? ? ? ? ? ? ? ? ? ab
> xy ? ? ? ? ? ? ?101 ? ? ? ? ? ? ? ? ? ? ab
> xy ? ? ? ? ? ? ?102 ? ? ? ? ? ? ? ? ? ? ab
> xy ? ? ? ? ? ? ?103 ? ? ? ? ? ? ? ? ? ? ab
>
>
> I tried strsplit but I couldn't figure out how to convert the list I
get into a data.frame.
>
> I just need a function like read.table. But it seems that read.table only
can handle files, not vectors...

Using textConnection() it can handle character vectors:
> DF <- read.table(textConnection(x), sep = "_"); DF
  V1  V2 V3
1 xy 100 ab
2 xy 101 ab
3 xy 102 ab
4 xy 103 ab