Manuel,
This looks like a bug in 'raster' that I think I have fixed in version
1.5-13 (should be available on R-Forge in 24 hrs or so).
As a work around, you can save ascii files to binary (once):
predictores<- writeRaster(predictores, 'predictores.grd' )
# or
predictores<- writeRaster(predictores, 'predictores.tif' )
and then in the script use:
predictores<- brick('predictores.grd')
# or
predictores<- brick('predictores.tif')
This also has the advantage of being much faster.
Robert
On Sat, Oct 2, 2010 at 3:11 PM, Manuel Sp?nola<mspinola10 at gmail.com> wrote:
Dear list members,
I got this error in package "dismo".
fold<- kfold(bradypus, k=5)
bradytrain<- bradypus[fold != 1, ]
me<- maxent(predictores, bradytrain)
Error en .readRowsAscii(raster, rows[i], 1) : elemento 1 esta vacio;
la parte de la lista de argumentos '>' ha sido evaluada:
(startcol, 1)
Function maxent works perfect for "bradypus" (data frame with 116
observations), but it doesn't work for "bradytrain" when I use kfold
function.
"bradytrain" is also a data frame but with 93 observations. The message is
in Sapnish, but basically say that element 1 is empty.
Thank you very much in advance.
Best,
Manuel
--
Manuel Sp?nola, Ph.D.
Instituto Internacional en Conservaci?n y Manejo de Vida Silvestre
Universidad Nacional
Apartado 1350-3000
Heredia
COSTA RICA
mspinola at una.ac.cr
mspinola10 at gmail.com
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