R help - Jun 2009 - Smart way to check if a column with certain name exists in a data.frame

Hi,

I have a matrix or data.frame (df). When I would like to check if a column
named "x" exists, it becomes my habit to do the following:

if (length(which(colnames(df)=="x"))>0)

Is there any smarter way to do this? Thank you.

adschai

	[[alternative HTML version deleted]]

try:

'x' %in% colnames(df)

hth,
Kingsford

On Mon, Jun 22, 2009 at 9:17 PM, R_help Help<rhelpacc at gmail.com>
wrote:
> Hi,
>
> I have a matrix or data.frame (df). When I would like to check if a column
> named "x" exists, it becomes my habit to do the following:
>
> if (length(which(colnames(df)=="x"))>0)
>
> Is there any smarter way to do this? Thank you.
>
> adschai
>
> ? ? ? ?[[alternative HTML version deleted]]
>
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