[R] Setting name attributes to a vector - join?

Thomas W Blackwell tblackw at umich.edu
Mon Jul 21 22:35:36 CEST 2003


I assume that  cnd.names  is a vector of character strings and
landcov[ ,2] is a vector of integers in c(1:length(cnd.names).
Then
	foo <- cnd.names[landcov[ ,2]]

should be what you want.

-  tom blackwell  -  u michigan medical school  -  ann arbor  -

On Mon, 21 Jul 2003, Andy Bunn wrote:

> I have a vector of land cover class data from a GIS:
>
> > landcov[1:10,2] #the first ten examples of a large (100k+) object
>  1  2  3  4  5  6  7  8  9 10
> 12 12 01 12 01 15 15 15 15 15
>
> etc.
>
> I also have a lookup table for the class data that gives the cover type
> as a string:
>
> > cnd.names #the look up table, i.e., landcov[3,2] == 1 == "Montane
> Meadow"
>    CndVal                                          Cnddbname
> 1       1                                     Montane Meadow
> 2       2                    Sierran Mixed Coniferous Forest
> 3       3                            Mixed Montane Chaparral
> 4       4                            Jeffrey Pine-Fir Forest
> 5       5                           Sierran White Fir Forest
>
> etc.
>
> How can I create an object that has the string as its value?
>
> I.e., foo[3] <- "Montane Meadow"
> I tried using apply and a custom function but couldn't get it to work.
>
> I feel like this is trivial but am stuck fast.
>
> Thanks, Andy




More information about the R-help mailing list