R help - Oct 2004 - colClasses

Hi
I am trying to read a data frame from a text editor in to R. I want some
of the columns to be read in as "character" not numeric.
I figured that I can do that by using "colClasses" in 
"read.table"
command. However, I couldn't find out how to use 
"colClasses". e.g. say I have 5 column in the data file. I want 1st
and
3rd column to be read in as character. How can I define
this using colClasses?  (or is there a better way to do what I want?)
 
Thanks.
Zeynep
 
 

	[[alternative HTML version deleted]]

On Mon, 11 Oct 2004 16:21:31 -0400, "Kalaylioglu, Zeynep (IMS)"
<KalayliogluZ at imsweb.com> wrote:
>Hi
>I am trying to read a data frame from a text editor in to R. I want some
>of the columns to be read in as "character" not numeric.
>I figured that I can do that by using "colClasses" in 
"read.table"
>command. However, I couldn't find out how to use 
>"colClasses". e.g. say I have 5 column in the data file. I want
1st and
>3rd column to be read in as character. How can I define
>this using colClasses?  (or is there a better way to do what I want?)
The help page for read.table looks reasonably clear to me.  Wouldn't
colClasses = c('character', 'numeric', 'character',
'numeric',
'numeric')

work?

Duncan Murdoch

When using colClasses you need to specify the types of all the 
columns.  So assuming the other columns are numeric data, you could set

colClasses = c("character", "numeric",
"character", "numeric", "numeric")

-roger

Kalaylioglu, Zeynep (IMS) wrote:
> Hi
> I am trying to read a data frame from a text editor in to R. I want some
> of the columns to be read in as "character" not numeric.
> I figured that I can do that by using "colClasses" in 
"read.table"
> command. However, I couldn't find out how to use 
> "colClasses". e.g. say I have 5 column in the data file. I want
1st and
> 3rd column to be read in as character. How can I define
> this using colClasses?  (or is there a better way to do what I want?)
>  
> Thanks.
> Zeynep
>  
>  
> 
> 	[[alternative HTML version deleted]]
> 
> ______________________________________________
> R-help at stat.math.ethz.ch mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide!
http://www.R-project.org/posting-guide.html
>

I would try.
colClasses=c("character","numeric","character","numeric","numeric")

/E

Kalaylioglu, Zeynep (IMS) wrote:
>Hi
>I am trying to read a data frame from a text editor in to R. I want some
>of the columns to be read in as "character" not numeric.
>I figured that I can do that by using "colClasses" in 
"read.table"
>command. However, I couldn't find out how to use 
>"colClasses". e.g. say I have 5 column in the data file. I want
1st and
>3rd column to be read in as character. How can I define
>this using colClasses?  (or is there a better way to do what I want?)
> 
>Thanks.
>Zeynep
> 
> 
>
>	[[alternative HTML version deleted]]
>
>______________________________________________
>R-help at stat.math.ethz.ch mailing list
>https://stat.ethz.ch/mailman/listinfo/r-help
>PLEASE do read the posting guide!
http://www.R-project.org/posting-guide.html
>
>  
>

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"Kalaylioglu, Zeynep (IMS)" <KalayliogluZ at imsweb.com> writes:
> Hi
> I am trying to read a data frame from a text editor in to R. I want some
> of the columns to be read in as "character" not numeric.
> I figured that I can do that by using "colClasses" in 
"read.table"
> command. However, I couldn't find out how to use 
> "colClasses". e.g. say I have 5 column in the data file. I want
1st and
> 3rd column to be read in as character. How can I define
> this using colClasses?  (or is there a better way to do what I want?)
The easiest is probably

  read.table(....as.is=c(1,3)....)

but you could also do 

  cC <- rep(NA,5)
  cC[c(1,3)] <- "character"
  read.table(....colClasses=cC...)

which would be more readily generalized to "stranger" data types.

-- 
   O__  ---- Peter Dalgaard             Blegdamsvej 3  
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