I assume that what you want is a matrix from the dataframe that was read in:

> x <- read.table(textConnection("1 2 3
+ 4 5 6
+ 7 8 9"))
>
> x
  V1 V2 V3
1  1  2  3
2  4  5  6
3  7  8  9
> str(x)
'data.frame':   3 obs. of  3 variables:
 $ V1: int  1 4 7
 $ V2: int  2 5 8
 $ V3: int  3 6 9
> x.n <- as.numeric(x)  # not the way to do it
Error: (list) object cannot be coerced to type 'double'
No suitable frames for recover()
> x.n <- as.matrix(x)  # convert dataframe to matrix
> str(x.n)
 int [1:3, 1:3] 1 4 7 2 5 8 3 6 9
 - attr(*, "dimnames")=List of 2
  ..$ : NULL
  ..$ : chr [1:3] "V1" "V2" "V3"
> x.n
     V1 V2 V3
[1,]  1  2  3
[2,]  4  5  6
[3,]  7  8  9
>


On Sat, Feb 20, 2010 at 12:50 PM, wendy <wendy.qiao@utoronto.ca> wrote:

>
> Dear all,
>
> I am really new to R, and I have problem here. I searched around, but did
> not get a solution.
>
> I have a numetrix matrix (20 by 25) saved in .csv. I read it as
>
> >sx<-read.csv("sx.csv",header=F)
> Then I try to convert it to numeric using
>
> >sx<-as.numeric(sx)
> Error: (list) object cannot be coerced to type 'double'
> The class of sx is  "data.frame".
>
> I tried to unlist it as,
> s<-unlist(sx), but when I look at the dimension,
> > dim(s)
> NULL
>
> Can anyone tell me how should I load my data as a numeric matrix rather
> than
> "data.frame", or how to convert the data.frame matrix into numeric?
>
> Thank you very much.
> Wendy
> --
> View this message in context:
> http://n4.nabble.com/coerce-list-object-to-type-double-tp1562988p1562988.html
> Sent from the R help mailing list archive at Nabble.com.
>
> ______________________________________________
> 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<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?

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