I'm new at this, so please bear with me.
I am trying to get Krig (actually tps) results into a data frame at a
set of points.
Frankly, all I really need is to query the Krig on a specific XY pair
and return a result. I can carry the rest. I am using tps from the
fields package.
Here's the code I use to create the Krig object:
=========== Snip! ==============================dCurr <-
sqlQuery(ds,"select x,y,acmi50 from public.cc_output" )
fitCurr <- Tps(dCurr[1:2],dCurr$acmi50, scale.type="unscaled")
surface(fitCurr,type="C", extrap=TRUE, main="Median ACMI,
1961-1990",
xlab="", ylab="", levels=evens)
==============================================
Ultimately, I want a table of XY locations and their appropriate value
from the surface. From that, I can do further statistics.
The XY locations are a regular grid, although they may not be in the
final product. If they are a regular grid, I could use a loop to drive
the process.
How can I do this? I am baffled by the help file, and cannot tell what
to do.
In principle, I could read the code of the surface function and figure
out what it does, then do the same, but I am sure I am not the only
person who wants to do some analysis on the output of an interpolation
function.
I want to run rpart on a data frame containing 20 variables (or so),
some of which are interpolated from weather stations.
Thanks for any help you can provide,
Angus Carr.
