Hi folks,
I'm trying to implement an ecological niche factor analysis with octopus but
I have some problems. I think it is related to the fact I have No-data
values. Since it's a marine species, I have land areas where I have no-data
values. Can I have grids with no-data values?
The thing is I'm able to import the ascii grid (using import.asc) and I'm
even able to plot it (and see the image), so I guessed I have no problems
with the no-data values. If I checked the grid, I got this:
str(chl)
asc [1:1214, 1:761] NA NA NA NA NA NA NA NA NA NA ...
- attr(*, "xll")= num -18.6
- attr(*, "yll")= num 16.7
- attr(*, "cellsize")= num 0.05
- attr(*, "type")= chr "numeric"
It looks wrong, but it's OK since my first values are indeed NA. In fact,
besides the fact I'm able to plot it, I can calculate grid means and other
stats, so I think the problem is not here. Then, when I grouped all the
grids (with the as.kasc function), I got this:
str(env_maps)
Classes ?kasc? and 'data.frame': 923854 obs. of 13 variables:
$ : num NA NA NA NA NA NA NA NA NA NA ...
$ : num NA NA NA NA NA NA NA NA NA NA ...
$ : num NA NA NA NA NA NA NA NA NA NA ...
$ : num NA NA NA NA NA NA NA NA NA NA ...
$ : num NA NA NA NA NA NA NA NA NA NA ...
$ : num NA NA NA NA NA NA NA NA NA NA ...
$ : num NA NA NA NA NA NA NA NA NA NA ...
$ : num NA NA NA NA NA NA NA NA NA NA ...
$ : num NA NA NA NA NA NA NA NA NA NA ...
$ : num NA NA NA NA NA NA NA NA NA NA ...
$ : num NA NA NA NA NA NA NA NA NA NA ...
$ : num NA NA NA NA NA NA NA NA NA NA ...
$ : num NA NA NA NA NA NA NA NA NA NA ...
- attr(*, "cellsize")= num 0.05
- attr(*, "xll")= num -18.6
- attr(*, "yll")= num 16.7
- attr(*, "ncol")= int 1214
- attr(*, "nrow")= int 761
- attr(*, "type")= chr "numeric" "numeric" "numeric" "numeric" ...
Still looks wrong, but it shouldn't be. Then, I proceed with the data2enfa
function, that seemed to work. But in the next step, when I was calculating
the dudi.pca, it failed, with this error:
Error in `rownames<-`(`*tmp*`, value = c("1", "2", "3", "4", "5", "6", :
attempt to set rownames on object with no dimensions
I checked the data2enfa result and I got this:
List of 4
$ tab :'data.frame': 923854 obs. of 0 variables
$ pr : int [1:923854] 0 0 0 0 0 0 0 0 0 0 ...
$ index: int [1:923854] 1 2 3 4 5 6 7 8 9 10 ...
$ attr :Class 'mapattr' atomic [1:1] 0
.. ..- attr(*, "xll")= num -18.6
.. ..- attr(*, "yll")= num 16.7
.. ..- attr(*, "cellsize")= num 0.05
.. ..- attr(*, "nrow")= int 761
.. ..- attr(*, "ncol")= int 1214
- attr(*, "class")= chr "dataenfa"
When I check the $tab, I got this:
octopus.hab$tab
data frame with 0 columns and 923854 rows*
*And I have no idea of what's wrong.... any ideas? do you suggest anything?
Why do I have 0 columns and 923854 rows? Is that possible? Can the data2enfa
funcion deal with no-data values?
I tried the magagNAkasc, but doesn't work...
managNAkasc (env_maps)
Raster map of class "kasc":
Cell size: 0.05
Number of rows: 761
Number of columns: 1214
Variables measured:
1. : numeric
Error in .subset2(x, i, exact = exact) :
attempt to select less than one element
I have tried in Windows Vista and Linux (both R 2.10.1 and adehabitat v
1.83.
I'd appreciate any help!!
Thanks!!!
Consuelo
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