[R-sig-Geo] singular model fit

[Javier Leon Patino]

Dear list,

I am aware there are many post dealing with singular model variogram fits but I have not been able to fix my problem even after re-scaling the coordinates and variables.

I am using fit.variogram(gstat) on the file 'trans.csv' (attached) and have tried several values for the range, sill and nugget and different models. The following gives me an ok variogram (from visual plot) but still a 'singular model' warning.

library(sp)
library(gstat)
points <- read.csv("trans.csv")
coordinates(points)=~x+y
depth.ivgm <- vgm(model='Gau',range=1000, psill=var(points$ln_depth))
depth.vgm <- fit.variogram(variogram(ln_depth~x+y, points), model=depth.ivgm)

Any ideas on why I am getting a singular fit? Is it the small number of samples used?

Cheers,

Javier

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