R help - Mar 2012 - subsetting by cell value with a list

I would like to subset by dataframe by matching all rows that have any value
from a list of values.  I can get it to work if I have exactly one value,
I'm not
sure how to do it with a list of values though.

This works and gives me exactly one line:
my.df[ which( mydf$IDX==17)), ]

I would like to do something like this:
my.df[ which( mydf$IDX==c(17, 42), ]

Obviously that won't work, but I hope the meaning is clear.
What's the right way to express this?

	[[alternative HTML version deleted]]

> my.df <- data.frame(IDX=1:42, x=rnorm(1:42))
> my.df[my.df$IDX %in% c(17, 42), ]
   IDX          x
17  17 -0.5110095
42  42 -1.0686427

Garrett

On Thu, Mar 15, 2012 at 3:25 PM, Ed Siefker <ebs15242 at gmail.com>
wrote:
> I would like to subset by dataframe by matching all rows that have any
value
> from a list of values. ?I can get it to work if I have exactly one value,
> I'm not
> sure how to do it with a list of values though.
>
> This works and gives me exactly one line:
> my.df[ which( mydf$IDX==17)), ]
>
> I would like to do something like this:
> my.df[ which( mydf$IDX==c(17, 42), ]
>
> Obviously that won't work, but I hope the meaning is clear.
> What's the right way to express this?
>
> ? ? ? ?[[alternative HTML version deleted]]
>
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