R help - Nov 2009 - matching and extracting data

Dear all,
I have querry on how to extract the data by matching between two data set where
one has the same elements multiple times?
 
For example, I have two matrix X and Y.
> X
   [,1]    [,2]       [,3]
1  A     5          P
2  B      6         P
3  C     7         P
4  D     5         Q
5  E      6         Q
6  F      7         Q
7  G     5          R
8  H     6          R
9  I       7          S
10 J      5         S
11 K    6          T
12 L     7          T
 
and 
 
>Y       [,1]
1          P
2          Q
3          R
4          S
 
Now, I want to select and extract all the data of P, Q, R and S elements of
column 3 of X matrix by matching with column 1 of Y matrix like below:
 
> [,1]   [,2]       [,3]
1  A     5          P
2  B      6         P
3  C     7         P
4  D     5         Q
5  E      6         Q
6  F      7         Q
7  G     5          R
8  H     6          R
9  I       7          S
10 J      5         S
 
I guess, the answer might be simple but i am not getting way to figure out. And,
i have to select subset from very huge data set. So, i need some kinds of
automated procedure.
If some one can help me, it will be great
 
Thanks in advance.
 
Sincerely,
Ram Kumar Basnet
 


      
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On 11/27/2009 10:25 AM, ram basnet wrote:
> Dear all,
> I have querry on how to extract the data by matching between two data set
where one has the same elements multiple times?
>  
> For example, I have two matrix X and Y.
>> X
>    [,1]    [,2]       [,3]
> 1  A     5          P
> 2  B      6         P
> 3  C     7         P
> 4  D     5         Q
> 5  E      6         Q
> 6  F      7         Q
> 7  G     5          R
> 8  H     6          R
> 9  I       7          S
> 10 J      5         S
> 11 K    6          T
> 12 L     7          T
>  
> and 
>  
>> Y       [,1]
> 1          P
> 2          Q
> 3          R
> 4          S
>  
> Now, I want to select and extract all the data of P, Q, R and S elements of
column 3 of X matrix by matching with column 1 of Y matrix like below:
>  
>> [,1]   [,2]       [,3]
> 1  A     5          P
> 2  B      6         P
> 3  C     7         P
> 4  D     5         Q
> 5  E      6         Q
> 6  F      7         Q
> 7  G     5          R
> 8  H     6          R
> 9  I       7          S
> 10 J      5         S
>  
> I guess, the answer might be simple but i am not getting way to figure out.
And, i have to select subset from very huge data set. So, i need some kinds of
automated procedure.
> If some one can help me, it will be great
> subset(X, X[,3] %in% Y[,1])
      [,1] [,2] [,3]
 [1,] "A"  "5"  "P"
 [2,] "B"  "6"  "P"
 [3,] "C"  "7"  "P"
 [4,] "D"  "5"  "Q"
 [5,] "E"  "6"  "Q"
 [6,] "F"  "7"  "Q"
 [7,] "G"  "5"  "R"
 [8,] "H"  "6"  "R"
 [9,] "I"  "7"  "S"
[10,] "J"  "5"  "S"
> Thanks in advance.
>  
> Sincerely,
> Ram Kumar Basnet
>  
> 
> 
>       
> 	[[alternative HTML version deleted]]
> 
> 
> 
> ------------------------------------------------------------------------
> 
> ______________________________________________
> R-help at r-project.org mailing list
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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.

-- 
Chuck Cleland, Ph.D.
NDRI, Inc. (www.ndri.org)
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On Nov 27, 2009, at 10:25 AM, ram basnet wrote:
> Dear all,
> I have querry on how to extract the data by matching between two  
> data set where one has the same elements multiple times?
>
> For example, I have two matrix X and Y.
>> X
>    [,1]    [,2]       [,3]
> 1  A     5          P
> 2  B      6         P
> 3  C     7         P
> 4  D     5         Q
> 5  E      6         Q
> 6  F      7         Q
> 7  G     5          R
> 8  H     6          R
> 9  I       7          S
> 10 J      5         S
> 11 K    6          T
> 12 L     7          T
>
> and
>
>> Y       [,1]
> 1          P
> 2          Q
> 3          R
> 4          S
>
> Now, I want to select and extract all the data of P, Q, R and S  
> elements of column 3 of X matrix by matching with column 1 of Y  
> matrix like below:
>
>> [,1]   [,2]       [,3]
> 1  A     5          P
> 2  B      6         P
> 3  C     7         P
> 4  D     5         Q
> 5  E      6         Q
> 6  F      7         Q
> 7  G     5          R
> 8  H     6          R
> 9  I       7          S
> 10 J      5         S
Perhaps (untested):

X[ X[,3] %in% Y[,1] , ]

Would have been tested if you had used dput or dump on your matrices.

-- 
David.
>
> I guess, the answer might be simple but i am not getting way to  
> figure out. And, i have to select subset from very huge data set.  
> So, i need some kinds of automated procedure.
> If some one can help me, it will be great
>
> Thanks in advance.
>
> Sincerely,
> Ram Kumar Basnet
>
>
>
>
> 	[[alternative HTML version deleted]]
>
> ______________________________________________
> 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