[R] Unfound objects in function

Colin Beale c.beale at macaulay.ac.uk
Tue Apr 18 10:02:12 CEST 2006

A couple of my functions that were working last week seem to have been
changed over the weekend and no longer work, but I can't understand why
not: it seems that objects defined at the start of the function are not
located further on in the function, when this worked fine before. An
example follows at the end, using the package spatstat, though the
problem seems more general. My only guess is that I've accidentally
changed something to do with the environment that functions are
searching in to exclude themselves, but if so I've no idea how I did or
how I can cancel it!

Thanks in advance,


library (spatstat)

kernelEst <- function (data, max.r = 10, edge = TRUE) {

  if (!is.ppp (data)) stop ("data must be a point process object")

  i <- 0.1
  diff    <- 1
  smo     <- 1

  while (diff > 0) {
    olddiff <- diff
    oldsmo  <- smo
    smo     <- density.ppp (data, sigma = 2 * i, edge = edge)
    lambda  <- smo[data]
    Ki      <- Kinhom (data[,data$window], lambda = lambda, r = seq (0,
max.r, length = 100), correction = "trans")
    diff    <- sum (Ki$theo - Ki$trans)
    i       <- i + 0.1
    if (i > max.r) stop ("no suitable kernel found within 0.2 to

  if (abs (olddiff) > abs (diff)) return (smo) else return (oldsmo)

data (simdat)
test <- kernelEst (simdat)
Error in while (diff > 0) { : missing value where TRUE/FALSE needed


> version
platform i386-pc-mingw32
arch     i386           
os       mingw32        
system   i386, mingw32  
major    2              
minor    2.1            
year     2005           
month    12             
day      20             
svn rev  36812          
language R

More information about the R-help mailing list