[R] position of a string in a data frame

[Frede Aakmann Tøgersen]

Try

 > foo <- data.frame(oid = 1:3, functions = c("mean", "sum", "sd"), type = c(TRUE, FALSE, TRUE))

> foo
  oid functions  type
1   1      mean  TRUE
2   2       sum FALSE
3   3        sd  TRUE

> foo == "sum"
       oid functions  type
[1,] FALSE     FALSE FALSE
[2,] FALSE      TRUE FALSE
[3,] FALSE     FALSE FALSE

> which(foo == "sum", arr.ind = TRUE)
     row col
[1,]   2   2
>

But can one risk this to fail if the class of some of the columns cannot be compared to a string?????

Yours sincerely / Med venlig hilsen


Frede Aakmann Tøgersen
Specialist, M.Sc., Ph.D.
Plant Performance & Modeling

Technology & Service Solutions
T +45 9730 5135
M +45 2547 6050
frtog at vestas.com
http://www.vestas.com

Company reg. name: Vestas Wind Systems A/S
This e-mail is subject to our e-mail disclaimer statement.
Please refer to www.vestas.com/legal/notice
If you have received this e-mail in error please contact the sender. 


> -----Original Message-----
> From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-project.org]
> On Behalf Of carol white
> Sent: 30. april 2014 13:42
> To: r-help at stat.math.ethz.ch
> Subject: [R] position of a string in a data frame
> 
> Hi,
> It might be a primitive question but how to find the position of a string in a
> data frame? Suppose I search the word "sum" (case insensitive) in a data
> frame and it is in the 7th row, 3rd column, how to retrieve the indices 7, 3? I
> tried to use grep with tapply but it doesn't work.
> 
> Many thanks
> 
> Carol
> 
> 	[[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.