[R] vlookup in R

Henrik Bengtsson hb at stat.berkeley.edu
Mon Mar 24 17:43:42 CET 2008


# Setup the translation map
transMap <- c(A="R", B="R", C="R", D="B", F="B");

# The input data
v3 <- c("A", "C", "D", "F", "A", "C", "B", "B", "B", "B", "A", "D");

# The translated data
v4 <- transMap[v3];

df2 <- data.frame(V3=v3, V4=v4);

I recommend you to read 'An Introduction to R' that comes with any R
installation.  There is a lot of useful stuff in there; it takes many
reads to grasp parts of it but it is worth it if you're going to use R
for more than, say, two weeks. You can find it via help.start().

/Henrik

On Mon, Mar 24, 2008 at 8:25 AM, Sachin J <sachinj.2006 at yahoo.com> wrote:
> Hi Henrique,
>
>  This is what I am trying to accomplish:
>  I want to read values in V1 and V2 and populate the column V4 with R or B based on the
>  values in V3 i.e. if its A,B,C then its R else if D,F then B. You can assume V1, V2 are dataframe1
>  and V3, V4 are in dataframe2 (note V4 is empty initially i.e. its a new column).
>
>  > df1
>  V1V2
>  A R
>  BR
>  CR
>  DB
>  FB
>
>  > df2
>
>  V3V4
>  AR
>  CR
>  DB
>  FB
>  AR
>  CR
>  BR
>  BR
>  BR
>  BR
>  AR
>  DB
>
>
>
>  Thanks in advance for your help.
>
>
>
>
>  ----- Original Message ----
>  From: Henrique Dallazuanna <wwwhsd at gmail.com>
>  To: Sachin J <sachinj.2006 at yahoo.com>
>  Cc: r-help at r-project.org
>  Sent: Monday, March 24, 2008 10:41:52 AM
>  Subject: Re: [R] vlookup in R
>
>  I think that merge is what you want:
>
>  set.seed(24032008)
>  x <- data.frame(ID=sample(10), Value=rnorm(10))
>  idx <- sample(5)
>  merge(idx, x, by.x=1, by.y=1)
>
>  On 24/03/2008, Sachin J <sachinj.2006 at yahoo.com> wrote:
>  > Hi,
>
> >
>  >  Is there are function similar to excel vlookup in R. Please let me know.
>  >
>
> >  Thanks,
>  >  Sachin
>  >
>  >
>  >      ____________________________________________________________________________________
>  >
>  >
>  >        [[alternative HTML version deleted]]
>  >
>  >  ______________________________________________
>
> >  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.
>  >
>
>
>
> --
>  Henrique Dallazuanna
>  Curitiba-Paraná-Brasil
>  25° 25' 40" S 49° 16' 22" O
>
>
>       ____________________________________________________________________________________
>
>
>         [[alternative HTML version deleted]]
>
>
> ______________________________________________
>  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.
>
>



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