R help - Sep 2007 - Data manipulation

Hello, 

I am beginner in R and I would like to solve the following problem:
Suppose that we have  three files to be red in R d1, d2, and d3
> d1
  id x1 x2
1  1  4  n
2  2  3  h
3  3  0  f
> d2
  id x1 x2
1  1  2  r
2  2  3  u
3  3  1  f
> d3
  id x1 x2
1  1  2  a
2  2  1  w

Is there any library or function that one can read this datasets like
for(i in 1:3)
 d[i] <- read.table(file=d[j].txt, header=T)

and is it possible to delete the header for each file and to have them in one
data frame like
> d
1   1  4  n
2   2  3  h
3   3  0  f
4   1  2  r
5   2  3  u
6   3  1  f
7  1  2  a
8  2  1  w
9  3  1  f

I really appreciate your help!
Stefo





       
---------------------------------

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use something like the following (untested)

files <- paste("C:/d", 1:3, ".txt", sep = "")
dats <- vector("list", 3)
for (i in 1:3) {
   dats[[i]] <- read.table(files[i], header = TRUE)
}
dats
do.call("rbind", dat)


I hope it helps.

Best,
Dimitris

----
Dimitris Rizopoulos
Ph.D. Student
Biostatistical Centre
School of Public Health
Catholic University of Leuven

Address: Kapucijnenvoer 35, Leuven, Belgium
Tel: +32/(0)16/336899
Fax: +32/(0)16/337015
Web: http://med.kuleuven.be/biostat/
      http://www.student.kuleuven.be/~m0390867/dimitris.htm


Quoting Stefo Ratino <sratino at yahoo.com>:
> Hello,
>
> I am beginner in R and I would like to solve the following problem:
> Suppose that we have  three files to be red in R d1, d2, and d3
>
>> d1
>   id x1 x2
> 1  1  4  n
> 2  2  3  h
> 3  3  0  f
>> d2
>   id x1 x2
> 1  1  2  r
> 2  2  3  u
> 3  3  1  f
>> d3
>   id x1 x2
> 1  1  2  a
> 2  2  1  w
>
> Is there any library or function that one can read this datasets like
> for(i in 1:3)
>  d[i] <- read.table(file=d[j].txt, header=T)
>
> and is it possible to delete the header for each file and to have   
> them in one data frame like
>
>> d
> 1   1  4  n
> 2   2  3  h
> 3   3  0  f
> 4   1  2  r
> 5   2  3  u
> 6   3  1  f
> 7  1  2  a
> 8  2  1  w
> 9  3  1  f
>
> I really appreciate your help!
> Stefo
>
>
>
>
>
>
> ---------------------------------
>
> 	[[alternative HTML version deleted]]
>
> ______________________________________________
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> PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>
>


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Hi

"Klaus Friis ?stergaard" <farremosen at gmail.com> napsal dne
16.10.2007
10:34:15:
> 
> 2007/10/15, Petr PIKAL <petr.pikal at precheza.cz>:
> Hi
> 
> 
> Well, let us put it another way. Do you want for each unique combination
> of Hole and Feature to subtract a value from one data frame, let us call
> it nom from another data frame, let us call it raw? If yes I assume you 
> have exactly same number of unique combinations of Hole and Feature 
values
> in both datasets.
> 
> In that case you can use such for cycle (although there can be other 
finer
> solutions)
> 
> for (i in 1:no.of.unique.levels ) {
> selection <- interaction(raw$hole, raw$feature) %in% 
interaction(nom$hole,
> nom$feature)[1]
> raw[selection,"value"] <-
raw[selection,"value"]-nom[i,"value"]
> }
> 
> I had to move on with the project and did a ruby script out side that 
put the 
> right values in the rawdata.
> 
> But I will surely return to look at this solution.
> 
> I question in the non table the combinations of Feature and Hole are 
unique is
> it possible to calculate this on the fly in R? 
Yes. If your next question is how, you can look at ?duplicated.

Regards
Petr
> 
> 
> 
> -- 
> Klaus F. ?stergaard, <farremosen(at)gmail dot com>