(no subject)

Dear R Users! I'm new in R! I've got a data.frame. For  
example:a<-data.frame(cbind(  0:1,   1:10))   X1 X2
1   0  1
2   1  2
3   0  3
4   1  4
5   0  5
6   1  6
7   0  7
8   1  8
9   0  9
10  1 10 Firstly i want to create combinations from  X2, for  
example:combn(a$X2,2) It&#39;s ok,
but secondly

I would like to get combinations from those X2 numbers only , where  
X1= 0. Could you help me? Thanks!

> combn( a[a$X1==0, "X2"] ,2)
      [,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9] [,10]
[1,]    1    1    1    1    3    3    3    5    5     7
[2,]    3    5    7    9    5    7    9    7    9     9

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The most excellent Posting Guide is a font of wisdom in other areas as  
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David Winsemius, MD
Alameda, CA, USA

Hi,
Try this:
dat1<-read.table(text="
1?? 0? 1
2?? 1? 2
3?? 0? 3
4?? 1? 4
5?? 0? 5
6?? 1? 6
7?? 0? 7
8?? 1? 8
9?? 0? 9
10? 1 10 
",sep="",header=FALSE)
?dat2<-dat1[,-1]
combn((subset(dat2,V2==0))$V3,2)
???? [,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9] [,10]
[1,]??? 1??? 1??? 1??? 1??? 3??? 3??? 3??? 5??? 5???? 7
[2,]??? 3??? 5??? 7??? 9??? 5??? 7??? 9??? 7??? 9???? 9

A.K.



----- Original Message -----
From: Dik?n Szabolcs Andr?s <dikanszabolcs at freemail.hu>
To: R-help at r-project.org
Cc: 
Sent: Sunday, August 19, 2012 8:14 PM
Subject: [R] (no subject)

Dear R Users! I'm new in R! I've got a data.frame. For example:a<-data.frame(cbind(? 0:1,?  1:10))?  X1 X2
1?  0? 1
2?  1? 2
3?  0? 3
4?  1? 4
5?  0? 5
6?  1? 6
7?  0? 7
8?  1? 8
9?  0? 9
10? 1 10 Firstly i want to create combinations from? X2, for example:combn(a$X2,2) It's ok, butsecondly I would like to get combinations from those X2 numbers only , where X1= 0. Could you help me? Thanks!? ? ? ? ? 
??? [[alternative HTML version deleted]]

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