[R] Error using Tsp

[W. C. Thacker]

Hello all,

My first try with the fields library's Tsp function, trying to imitate 
the ozone example with my data, has resulted in the following error 
message:

> fit <- Tps(as.matrix(all.60[,5:6]),as.vector(all.60[,3]))
Error in if (den < 0) { : missing value where logical needed
In addition: Warning messages: 
1: GCV search gives a minumum at the endpoints of the grid search in: 

Krig.find.gcvmin(info, lambda.grid, gcv.grid$GCV.one, Krig.fgcv.one,  
2: no finite arguments to max; returning -Inf 

What does the error message mean?  What am I doing wrong?

Thanks,

Carlisle

PS:  all.60 is a dataframe containing oceanographic data from 60m
depth. 
 Columns 5 and 6 are longitude and latitude and column 3 is
temperature.

PPS:  I'm using Windows XP
> version
         _              
platform i386-pc-mingw32
arch     i386           
os       mingw32        
system   i386, mingw32  
status                  
major    1              
minor    6.1            
year     2002           
month    11             
day      01             
language R