[R-sig-Geo] Importing raster data from Arcview to R for fitting a ppm

[adrian at maths.uwa.edu.au]

Honey Giroday <girodayh at unbc.ca> writes:

> I am a relatively new UseR and am currently using R 2.5.1 on a
> linux operating system (I am connected to the linux system via
> remote desktop connection).  I am trying to import a raster
> dataset (in ASCII format) to fit as a covariate in a ppm.

ppm is part of the 'spatstat' package. It's usually best to contact the
authors of the package if you have trouble.

My first comment is that you do not seem to be running the current version
of spatstat. The current version is spatstat 1.13-0 and this requires R
2.6.0 (see www.spatstat.org) so apparently the installation of R and
spatstat on your Linux system are out of date.

> However, I keep getting this error message every time I got to fit
> the model.
> "Warning message:
> Values of covariate "slope" were NA or undefined at 1% (1 out of 80812)
> of the quadrature points.

Although the message says 1% of values were NA, that number has been
rounded upward. The exact figure is given in the parentheses: just ONE of
the quadrature points, out of 80812 quadrature points, gave an NA value.
This probably occurred at one of the corners of the window. Since it's
only one quadrature point that is problematic, this is probably not worth
worrying about.

I suggest you upgrade to the latest versions of R and spatstat and see if
the warning message is still present.

Adrian Baddeley
co-author of spatstat