indeed, on the example file, this works fine.
library(foreign)
data <- read.dbf('theme1.dbf')
data$AminB <- data$A - data$B
file.remove('theme1.dbf')
write.dbf(data, 'theme1.dbf')
if the dbf is too large you could you use a database to import the
dbf, add the column, export again. Perhaps sqlite
Hi,
This should work:
my_SPDF <- readShapeSpatial("theme1.shp")
my_s...@data$ab<-my_s...@data$a-my_spdf@data$B
writeSpatialShape(my_SPDF, "mynewfile")
Cheers,
Jonathan Maynard
On Tue, Feb 24, 2009 at 6:37 AM, Alexander Brenning
wrote:
> Hi there,
>
> to throw in two more alternatives, there
Hi there,
to throw in two more alternatives, there are functions read.dbf and
write.dbf in packages shapefiles and foreign (see help files for
examples; the functions differ between the two packages despite having
the same name).
Remember that operations on the shapefile attributes only affe
