R help - Dec 2006 - Better way to change the name of a column in a dataframe?

Hello R users --

 

If I have a dataframe such as the following, named "frame" with the
columns intended to be named col1 through col6,

 
> frame
     col1 col2 cmlo3 col4 col5 col6

[1,]    3   10     2    6    5    7

[2,]    6    8     4   10    7    1

[3,]    7    5     1    3    1    8

[4,]   10    6     5    4    9    2

 

and I want to correct or otherwise change the name of one of the
columns, I can do so with 

 
> dimnames(frame)[[2]][which(dimnames(frame)[[2]]=="cmlo3")] <-
"col3"
 

which renames the offending column:

 
> frame
     col1 col2 col3 col4 col5 col6

[1,]    3   10    2    6    5    7

[2,]    6    8    4   10    7    1

[3,]    7    5    1    3    1    8

[4,]   10    6    5    4    9    2

 

This seems cumbersome and not very intuitive.  How can one accomplish
this more simply?

 

With thanks for any suggestions,

 

Ben Fairbank


	[[alternative HTML version deleted]]

Ben,

Unless I misunderstand your question, why not just use

names(frame)[3]<-"col3"

"Ben Fairbank" <BEN at SSANET.COM> wrote:
> [...] I want to correct or otherwise change the name of one of the
> columns, I can do so with 
> 
> > dimnames(frame)[[2]][which(dimnames(frame)[[2]]=="cmlo3")]
<- "col3"
> 
> This seems cumbersome and not very intuitive.  How can one accomplish
> this more simply?
This is slightly simpler than what you had:

      names(frame)[which(names(frame) == "cmlo3")] <-
"col3"

There are probably better ways still. 

-- 
Mike Prager, NOAA, Beaufort, NC
* Opinions expressed are personal and not represented otherwise.
* Any use of tradenames does not constitute a NOAA endorsement.

Hi,

names(frame)[names(frame) == "cmlo3"] <- "col3"

should also work

Cheers

Andrew

On Thu, Dec 14, 2006 at 05:05:20PM -0500, Mike Prager
wrote:
> "Ben Fairbank" <BEN at SSANET.COM> wrote:
> 
> > [...] I want to correct or otherwise change the name of one of the
> > columns, I can do so with 
> > 
> > >
dimnames(frame)[[2]][which(dimnames(frame)[[2]]=="cmlo3")] <-
"col3"
> > 
> > This seems cumbersome and not very intuitive.  How can one accomplish
> > this more simply?
> 
> This is slightly simpler than what you had:
> 
>       names(frame)[which(names(frame) == "cmlo3")] <-
"col3"
> 
> There are probably better ways still. 
> 
> -- 
> Mike Prager, NOAA, Beaufort, NC
> * Opinions expressed are personal and not represented otherwise.
> * Any use of tradenames does not constitute a NOAA endorsement.
> 
> ______________________________________________
> 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
> and provide commented, minimal, self-contained, reproducible code.
-- 
Andrew Robinson  
Department of Mathematics and Statistics            Tel: +61-3-8344-9763
University of Melbourne, VIC 3010 Australia         Fax: +61-3-8344-4599
http://www.ms.unimelb.edu.au/~andrewpr
http://blogs.mbs.edu/fishing-in-the-bay/

Ben Fairbank wrote:
> Hello R users --
> 
>  
> 
> If I have a dataframe such as the following, named "frame" with
the
> columns intended to be named col1 through col6,
> 
>  
> 
>> frame
> 
>      col1 col2 cmlo3 col4 col5 col6
> 
> [1,]    3   10     2    6    5    7
> 
> [2,]    6    8     4   10    7    1
> 
> [3,]    7    5     1    3    1    8
> 
> [4,]   10    6     5    4    9    2
> 
>  
> 
> and I want to correct or otherwise change the name of one of the
> columns, I can do so with 
> 
>  
> 
>> dimnames(frame)[[2]][which(dimnames(frame)[[2]]=="cmlo3")]
<- "col3"
> 
>  
> 
> which renames the offending column:
> 
>  
> 
>> frame
> 
>      col1 col2 col3 col4 col5 col6
> 
> [1,]    3   10    2    6    5    7
> 
> [2,]    6    8    4   10    7    1
> 
> [3,]    7    5    1    3    1    8
> 
> [4,]   10    6    5    4    9    2
> 
>  
> 
> This seems cumbersome and not very intuitive.  How can one accomplish
> this more simply?
> 
>  
well I would simply use

names(frame)[3] = 'col3'

(supposing you know the column number of your offending column anyway).

And there is the rename.vars() function in the gdata package.
-Don

At 11:39 AM -0600 12/14/06, Ben Fairbank wrote:
>Hello R users --
>
>
>
>If I have a dataframe such as the following, named "frame" with
the
>columns intended to be named col1 through col6,
>
>
>
>>  frame
>
>      col1 col2 cmlo3 col4 col5 col6
>
>[1,]    3   10     2    6    5    7
>
>[2,]    6    8     4   10    7    1
>
>[3,]    7    5     1    3    1    8
>
>[4,]   10    6     5    4    9    2
>
>
>
>and I want to correct or otherwise change the name of one of the
>columns, I can do so with
>
>
>
>>  dimnames(frame)[[2]][which(dimnames(frame)[[2]]=="cmlo3")]
<- "col3"
>
>
>
>which renames the offending column:
>
>
>
>>  frame
>
>      col1 col2 col3 col4 col5 col6
>
>[1,]    3   10    2    6    5    7
>
>[2,]    6    8    4   10    7    1
>
>[3,]    7    5    1    3    1    8
>
>[4,]   10    6    5    4    9    2
>
>
>
>This seems cumbersome and not very intuitive.  How can one accomplish
>this more simply?
>
>
>
>With thanks for any suggestions,
>
>
>
>Ben Fairbank
>
>
>	[[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
>and provide commented, minimal, self-contained, reproducible code.

-- 
--------------------------------------
Don MacQueen
Environmental Protection Department
Lawrence Livermore National Laboratory
Livermore, CA, USA