[R-sig-Geo] change a value in the dataframe of a SPDF

[Ingo Holz]

Hi,

 I changed a specific value in the dataframe of a SpatialPolygonsDataFrame 
in the following way:

 SPDF[["Name"]][1] <- 1

 This needed a very long time (about 10 seconds).

 I have two questions:
   Is there a faster way to do it?
   Why did it need that much time like I did it?

 Thank you,
 Ingo