[R] how to use a column name from the data frame in the function

[Jeff Newmiller]

Please don't post in HTML format... it messes with code examples.

Use character indexing (please read the Introduction to R... again if necessary).

myf <- function(df, colname){
  df[ ,colname ]
}

colname  <- "a"
myf(m,colname)

Until you learn simple R syntax, I strongly recommend avoiding writing tricky code that plays with names of variables.

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Sent from my phone. Please excuse my brevity.

song song <rprojecthelp at gmail.com> wrote:
>for example I have data frame m as below:
>
>m=as.data.frame(outer(1:5,6:9))
>colnames(m)=c('a','b','c','d')
>
>and I define the function
>
>myf=function(df, colname){
>
>   suppose colname is a, then:
>   how can I get the column 'a'
>   and how to get the colname as a string, 'a'
>
>}
>
>Thank you!
>
>	[[alternative HTML version deleted]]
>
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