[R] table lookup n R

[Petr Pikal]

Hi

On 13 Jul 2004 at 14:34, Anne wrote:

> Hello R helpers!
> I looked  but did not find a table-lookup R-utility. I could use a
> loop to do the job (old FORTRAN/C habits die hard) but if I have a big
> table in which I have to search for the values corresponding to a
> vector, I end up logically with a double loop. Is there already such a
> utility? Otherwise, is there a way without loops?

Well, if I understand you correctly, you want to find something in 
your table (data.frame)

try:

your.table==your.vector
to get TRUE/FALSE table with same dimensions as your table

and

which(your.table==your.vector, arr.ind=T)

to obtain row/col indices of TRUE values

In case you want something else please try to be more specific.

Cheers
Petr

> 
> Thanks as always
> Anne
> ----------------------------------------------------
> Anne Piotet
> Tel: +41 79 359 83 32 (mobile)
> Email: anne.piotet at m-td.com
> ---------------------------------------------------
> M-TD Modelling and Technology Development
> PSE-C
> CH-1015 Lausanne
> Switzerland
> Tel: +41 21 693 83 98
> Fax: +41 21 646 41 33
> --------------------------------------------------
> 
>  [[alternative HTML version deleted]]
> 
> ______________________________________________
> R-help at stat.math.ethz.ch mailing list
> https://www.stat.math.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide!
> http://www.R-project.org/posting-guide.html

Petr Pikal
petr.pikal at precheza.cz