[R-sig-Geo] subseting an spatial polygons data frame

[Agustin Lobo]

Answering to myself:

This works fine:

plot(x[x at data$CODI_EQP!=413,])
plot(x[row.names(x)==20,])

Agus

Agustin Lobo wrote:
> I want to discard few polygons from an
> sp. poly. DF. I'm trying things such as:
>  > str(x,max.level=2)
> Formal class 'SpatialPolygonsDataFrame' [package "sp"] with 5 slots
>   ..@ data       :'data.frame':    42 obs. of  9 variables:
>   ..@ polygons   :List of 42
>   ..@ plotOrder  : int [1:42] 32 35 38 1 8 29 33 26 27 31 ...
>   ..@ bbox       : num [1:2, 1:2] 437951 4605986 459732 4633538
>   .. ..- attr(*, "dimnames")=List of 2
>   ..@ proj4string:Formal class 'CRS' [package "sp"] with 1 slots
>  >
>  > x <- subset(x,row.names(x)!="1")
> Error in `[.data.frame`(x at data, i, j, ..., drop = FALSE) :
>   undefined columns selected
> 
> but the output of row.names(x)!="1"
> is correct, what am I doing wrong?  Is subset() (from maptools) not 
> appropriate for objects of type  SPDF ?
> 
> Thanks
> 
> Agus
>