Common elements in columns

Another way of solving the problem:

set.seed(1)
df1<-data.frame(C1=sample(LETTERS[1:25],20,replace=FALSE),value=sample(50,20,replace=FALSE))
set.seed(15)
df2<-data.frame(C1=sample(LETTERS[1:25],15,replace=FALSE),C2=1:15)
set.seed(3)
df3<-data.frame(C1=sample(LETTERS[1:10],10,replace=FALSE),B1=rnorm(10,3))
set.seed(5)
df4<-data.frame(C1=sample(LETTERS[1:15],10,replace=FALSE),A2=rnorm(10,15))

x <- list(df1$C1, df2$C1, df3$C1, df4$C1)
Reduce(intersect, x)

[1] "G" "E" "H" "J"

On Mon, Sep 3, 2012 at 7:01 AM, Silvano Cesar da Costa <silvano at uel.br>
wrote:

Hi Arun,

it's exactly what I wanted.

Thanks a lot,

Hi,
May be this might help:

set.seed(1)
df1<-data.frame(C1=sample(LETTERS[1:25],20,replace=FALSE),value=sample(50,20,replace=FALSE))
set.seed(15)
df2<-data.frame(C1=sample(LETTERS[1:25],15,replace=FALSE),C2=1:15)
set.seed(3)
df3<-data.frame(C1=sample(LETTERS[1:10],10,replace=FALSE),B1=rnorm(10,3))
set.seed(5)
df4<-data.frame(C1=sample(LETTERS[1:15],10,replace=FALSE),A2=rnorm(10,15))
df1$C1[df1$C1%in%df2$C1[df2$C1%in%df3$C1[df3$C1%in%df4$C1]]]
#[1] G E H J
A.K.



----- Original Message -----
From: Silvano Cesar da Costa <silvano at uel.br>
To: r-help at r-project.org
Cc:
Sent: Sunday, September 2, 2012 7:05 PM
Subject: [R] Common elements in columns

Hi,

I have 4 files with 10000 individuals in each file and 10 columns each.
One of the columns, say C1, may have elements in common with the other
columns C1 of other files.

If I have only 2 files, I can do this check with the command:

data1[data1 %in% data2]
data2[data2 %in% data1]

How do I check which common elements in the columns of C1 4 files?

Thanks,

---------------------------------------------
Silvano Cesar da Costa

Universidade Estadual de Londrina
Centro de Ci?ncias Exatas
Departamento de Estat?stica

Fone: (43) 3371-4346

---------------------------------------------
Silvano Cesar da Costa

Universidade Estadual de Londrina
Centro de Ci?ncias Exatas
Departamento de Estat?stica

Fone: (43) 3371-4346

--
Jim Holtman
Data Munger Guru

What is the problem that you are trying to solve?
Tell me what you want to do, not how you want to do it.