[R] How can I delete components in a column ?

[Marc Schwartz (via MN)]

On Mon, 2006-10-09 at 17:15 +0200, Yen Ngo wrote:
> Hi all R-helpers,
>    
>   i am a new R-user and have problem with deleting some components in a column. I have a dataset like
>    
>   Name  Id        x
>            empty   2
>            empty   3
>   a        none    2
>   b        none    3
>   d       none     2
>   ad      cfh       4
>   bf       cdt       5
>            empty   2
>            empty   2
>   gf      cdh       4
>   d       none     5
>    
>   and want to eliminate all components that have id=none and empty . The remaining data should be
>    
>   Name  Id       x
>   ad       cfh      4
>   bf        cdt      5
>   gf        cdh     4
>    
>   How can I do this ? The components with id=empty have no name.
>    
>   Thanks in advance,
>   Regards,
>   Yen

The easiest way is the use the subset() function. Presuming that your
data frame is called 'DF':

  NewDF <- subset(DF, !Id %in% c("empty", "none"))

The second argument, using a logical negation of the "%in%" function,
tells subset to only select those rows where the "Id" column does not
contain either "empty" or "none".

See ?subset and ?"%in%"

HTH,

Marc Schwartz