[R] select subset based on another variable

2010-05-13 Thread Carrie Li
Hi, dear R-helpers,

I have a simple question regarding selecting subset of a variable based on
another variable.
Here is the example:

xx=rnorm(10)
id=sample(1:10, 10)

temp=c(6, 1, 8, 2)

Now, all I want is xx's that their id are 6, 1, 8, 2, instead of the
position.

Any suggestions ?

Thank you all your help !!

Carrie

[[alternative HTML version deleted]]

__
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.


Re: [R] select subset based on another variable

2010-05-13 Thread David Winsemius


On May 13, 2010, at 9:48 AM, Carrie Li wrote:


Hi, dear R-helpers,

I have a simple question regarding selecting subset of a variable  
based on

another variable.
Here is the example:

xx=rnorm(10)
id=sample(1:10, 10)

temp=c(6, 1, 8, 2)

Now, all I want is xx's that their id are 6, 1, 8, 2, instead of the
position.

Any suggestions ?


xx[temp]

--
David.


Thank you all your help !!

Carrie

[[alternative HTML version deleted]]

__
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.


David Winsemius, MD
West Hartford, CT

__
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.


Re: [R] select subset based on another variable

2010-05-13 Thread Henrique Dallazuanna
Try this:

 subset(xx, id %in% temp)

On Thu, May 13, 2010 at 10:48 AM, Carrie Li carrieands...@gmail.com wrote:

 Hi, dear R-helpers,

 I have a simple question regarding selecting subset of a variable based on
 another variable.
 Here is the example:

 xx=rnorm(10)
 id=sample(1:10, 10)

 temp=c(6, 1, 8, 2)

 Now, all I want is xx's that their id are 6, 1, 8, 2, instead of the
 position.

 Any suggestions ?

 Thank you all your help !!

 Carrie

[[alternative HTML version deleted]]

 __
 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.




-- 
Henrique Dallazuanna
Curitiba-Paraná-Brasil
25° 25' 40 S 49° 16' 22 O

[[alternative HTML version deleted]]

__
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.


Re: [R] select subset based on another variable

2010-05-13 Thread jim holtman
try this:

 xx=rnorm(10)
 id=sample(1:10, 10)

 temp=c(6, 1, 8, 2)
 xx[match(temp, id)]
[1]  0.4874291 -0.6212406  1.5117812  0.5757814
 xx
 [1] -0.8204684  0.4874291  0.7383247  0.5757814 -0.3053884  1.5117812
0.3898432 -0.6212406 -2.2146999
[10]  1.1249309
 id
 [1]  5  6  4  2 10  8  9  1  7  3



On Thu, May 13, 2010 at 9:48 AM, Carrie Li carrieands...@gmail.com wrote:

 Hi, dear R-helpers,

 I have a simple question regarding selecting subset of a variable based on
 another variable.
 Here is the example:

 xx=rnorm(10)
 id=sample(1:10, 10)

 temp=c(6, 1, 8, 2)

 Now, all I want is xx's that their id are 6, 1, 8, 2, instead of the
 position.

 Any suggestions ?

 Thank you all your help !!

 Carrie

[[alternative HTML version deleted]]

 __
 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.htmlhttp://www.r-project.org/posting-guide.html
 and provide commented, minimal, self-contained, reproducible code.




-- 
Jim Holtman
Cincinnati, OH
+1 513 646 9390

What is the problem that you are trying to solve?

[[alternative HTML version deleted]]

__
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.


Re: [R] select subset based on another variable

2010-05-13 Thread David Winsemius


On May 13, 2010, at 9:55 AM, David Winsemius wrote:



On May 13, 2010, at 9:48 AM, Carrie Li wrote:


Hi, dear R-helpers,

I have a simple question regarding selecting subset of a variable  
based on

another variable.
Here is the example:

xx=rnorm(10)
id=sample(1:10, 10)

temp=c(6, 1, 8, 2)

Now, all I want is xx's that their id are 6, 1, 8, 2, instead of the
position.

Any suggestions ?


xx[temp]


I may have jumped the gun, but on reflection I am not sure that your  
question was at all clear. Is the first item desired the 6th item of  
xx or the xx item referenced by the 6th item of id? You gave a  
specification that would not allow any of us to check, since you did  
not specify a random seed. We have no way of seeing what either of  
your xx or id vectors look like since you did not provide either them  
or the desired output. If it were the second specification then  
consider this:


 set.seed(123)
 xx=rnorm(10)
 id=sample(1:10, 10)

 temp=c(6, 1, 8, 2)
 xx;id
 [1] -0.56047565 -0.23017749  1.55870831  0.07050839  0.12928774   
1.71506499

 [7]  0.46091621 -1.26506123 -0.68685285 -0.44566197
 [1]  9  7  6 10  4  8  3  2  1  5
 xx[id[temp]]
[1] -1.2650612 -0.6868529 -0.2301775  0.4609162



--
David.


Thank you all your help !!

Carrie

[[alternative HTML version deleted]]

__
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.


David Winsemius, MD
West Hartford, CT

__
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.


David Winsemius, MD
West Hartford, CT

__
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.