R help - Apr 2009 - Selecting vector elements using other vectors

Dear R-Help,

I have a data frame and a vector

df=data.frame(Letter=c("Z","Q","R","A","E","F"),
Number=c(11,32,4,1,9,3))
v=c("C","Q","R","A","E")
>From df, I'd like to construct a subset of the field "Number",
with
deletions dictated by the vector, v, of letters.  I've succeeded in doing
this for a single deletion (for example Letter="Q") with the following

df$Number[df$Letter != v[2]]

but am struggling do more than one at a time.  For example, 

df$Number[df$Letter != v[2:5]] 

gives the error:   Warning messages: 1: Is.na(e1) | is.na(e2) : longer
object length is not a multiple of shorter object length 2: In.....  Perhaps
there is a much easier way to approach this...

Any help would be greatly appreciated!

Alastair
-- 
View this message in context:
http://www.nabble.com/Selecting-vector-elements-using-other-vectors-tp23296130p23296130.html
Sent from the R help mailing list archive at Nabble.com.

See

 	?is.element
 	?%in%

HTH,

Chuck
On Wed, 29 Apr 2009, 00alastair00 wrote:
>
> Dear R-Help,
>
> I have a data frame and a vector
>
>
df=data.frame(Letter=c("Z","Q","R","A","E","F"),
Number=c(11,32,4,1,9,3))
> v=c("C","Q","R","A","E")
>
>> From df, I'd like to construct a subset of the field
"Number", with
> deletions dictated by the vector, v, of letters.  I've succeeded in
doing
> this for a single deletion (for example Letter="Q") with the
following
>
> df$Number[df$Letter != v[2]]
>
> but am struggling do more than one at a time.  For example,
>
> df$Number[df$Letter != v[2:5]]
>
> gives the error:   Warning messages: 1: Is.na(e1) | is.na(e2) : longer
> object length is not a multiple of shorter object length 2: In..... 
Perhaps
> there is a much easier way to approach this...
>
> Any help would be greatly appreciated!
>
> Alastair
> -- 
> View this message in context:
http://www.nabble.com/Selecting-vector-elements-using-other-vectors-tp23296130p23296130.html
> Sent from the R help mailing list archive at Nabble.com.
>
> ______________________________________________
> 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.
>
Charles C. Berry                            (858) 534-2098
                                             Dept of Family/Preventive Medicine
E mailto:cberry at tajo.ucsd.edu	            UC San Diego
http://famprevmed.ucsd.edu/faculty/cberry/  La Jolla, San Diego 92093-0901