[Gstat-info] Re: two rapid questions: change column name in a slot and overlay(SpatialPixels, SpatialPoints)

[Edzer Pebesma]

Dear Giovanni,

r-sig-geo is the more appropriate list for questions of this kind.
--
Edzer

G. Allegri wrote:
> Solved the second questions. I didn't understood that overlay returns
> the x index values at y locations...
> The first remains.
>
> 2008/3/12, G. Allegri <giohappy at gmail.com>:
>   
>> I've also tried:
>>
>>  overlay(EceZKRIG0_3[,"V151"],t0)
>>
>>  but it doesn't help
>>
>>  2008/3/12, G. Allegri <giohappy at gmail.com>:
>>
>>     
>>> I've two questions more (I will stop soon!):
>>>       
>>  >
>>  >  1 - I'm trying to change a column name of the data slot of a
>>  >  SpatialPixelsDataFrame
>>  >  I've added the column this way:
>>  >  slot(EceZKRIG0_3,"data")[,index]<-Sim_mean_approx[[2]]
>>  >
>>  >  The column added is V151 (as 151 is the actual index).
>>  >  I want to rename it, and I've tried:
>>  >
>>  >  names(slot(EceZKRIG0_3,"data")[index])<-"Mean_approx"
>>  >
>>  >  No errors are raised, but the column remain V151. What's wrong?
>>  >
>>  >  2 - I need to extract the values from a SpatialPixelsDataFrame (SP1)
>>  >  at SpatialPointsDataFrame (SP2) locations.
>>  >  I've simply used:
>>  >
>>  >  overlay(EceZKRIG0_3,t0)
>>  >
>>  >  where EceZKRIG0_3 is SP1 and t0 is SP2. It returns some numerical
>>  >  values that I don't know what they refer to. How can I indicate that I
>>  >  want to extract a certain data column from SP1 (V151, in this case)?
>>  >
>>  >  Thanks very much, as usual.
>>  >  Giovanni
>>  >
>>
>>     
> _______________________________________________
> Gstat-info mailing list
> Gstat-info at geo.uu.nl
> http://mailman.geo.uu.nl/mailman/listinfo/gstat-info
>