R help - Jun 2010 - charactor matrix convert to numeric matrix

Hello R experts,
can you tell me a simple way to convert a charactor matrix to numeric matrix?
if I use as.numeric, the matrix is converted to a vector.

a<-cbind(c("23","54","65"),c("1","2","3"))
a
     [,1] [,2]
[1,] "23" "1" 
[2,] "54" "2" 
[3,] "65" "3" 

 as.numeric(a)
[1] 23 54 65  1  2  3

thanks
Jian





      
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try this:
>
a<-cbind(c("23","54","65"),c("1","2","3"))
> a
     [,1] [,2]
[1,] "23" "1"
[2,] "54" "2"
[3,] "65" "3"
> mode(a) <- 'numeric'
> a
     [,1] [,2]
[1,]   23    1
[2,]   54    2
[3,]   65    3
>

On Wed, Jun 2, 2010 at 8:15 AM, Yuan Jian <jayuan2008 at yahoo.com>
wrote:
> Hello R experts,
> can you tell me a simple way to convert a charactor matrix to numeric
matrix?
> if I use as.numeric, the matrix is converted to a vector.
>
>
a<-cbind(c("23","54","65"),c("1","2","3"))
> a
> ???? [,1] [,2]
> [1,] "23" "1"
> [2,] "54" "2"
> [3,] "65" "3"
>
> ?as.numeric(a)
> [1] 23 54 65? 1? 2? 3
>
> thanks
> Jian
>
>
>
>
>
>
> ? ? ? ?[[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.
>
>


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

What is the problem that you are trying to solve?

Hi

you have several options

apply(a, 2, as.numeric)

matrix(as.numeric(a),3,2)

b<-as.numeric(a)
dim(b)<-c(3,2)

Regards
Petr


r-help-bounces at r-project.org napsal dne 02.06.2010 14:15:25:
> Hello R experts,
> can you tell me a simple way to convert a charactor matrix to numeric 
matrix?
> if I use as.numeric, the matrix is converted to a vector.
> 
>
a<-cbind(c("23","54","65"),c("1","2","3"))
> a
>      [,1] [,2]
> [1,] "23" "1" 
> [2,] "54" "2" 
> [3,] "65" "3" 
> 
>  as.numeric(a)
> [1] 23 54 65  1  2  3
> 
> thanks
> Jian
> 
> 
> 
> 
> 
> 
>    [[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.

Hi Jian,

Try

matrix(as.numeric(a), ncol = 2)

HTH,
Jorge


On Wed, Jun 2, 2010 at 8:15 AM, Yuan Jian <> wrote:
> Hello R experts,
> can you tell me a simple way to convert a charactor matrix to numeric
> matrix?
> if I use as.numeric, the matrix is converted to a vector.
>
>
a<-cbind(c("23","54","65"),c("1","2","3"))
> a
>      [,1] [,2]
> [1,] "23" "1"
> [2,] "54" "2"
> [3,] "65" "3"
>
>  as.numeric(a)
> [1] 23 54 65  1  2  3
>
> thanks
> Jian
>
>
>
>
>
>
>        [[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.
>
>
	[[alternative HTML version deleted]]