..Or in case there is no help,
any hint on a similarly implemented interpolation technique that can be
used in R and not in SAGA?

Working with fields::Tps function I have serious problems of performance
and memory.
As I understood, SAGA is much more bearable for raster computations.

Thanks in advance,
Piero

On 20 May 2012 13:06, piero campa <piero.campa@gmail.com> wrote:

> Dear list,
>
> after reading through "Spatio-temporal prediction of daily temperatures
> using time-series of MODIS LST images" (Hengl et al.,
> http://dx.doi.org/10.1007/s00704-011-0464-2), I wanted to try out these
> SAGA
> *grid_tools* modules to fill the gaps in my MODIS AOT datasets.
>
> I tried to follow what is done in the related script
> (http://spatial-analyst.net/book/HRtemp.R) but I think I am missing
> something, since my filled output is just identical to my input grid.
>
> I will report my steps by means of the usual /meuse/ dataset:
>
> data(meuse.grid)
>
> coordinates(meuse.grid) <- ~x+y
> gridded(meuse.grid) <- TRUE
> fullgrid(meuse.grid) <- TRUE
>
> # Create some hole
> meuse.grid$dist[meuse.grid$dist > .3] <- NA
>
> # Input File for SAGA
> writeGDAL(meuse.grid["dist"], "dist.sdat", "SAGA")
>
> # Run SAGA utility
> rsaga.get.usage(lib="grid_tools", module=7)
> rsaga.geoprocessor(lib="grid_tools", module=7,
> param=list(INPUT="dist.sgrd",
> RESULT="sp_dist.sgrd"))
> # = rsaga.close.gaps("dist.sgrd", "sp_dist.sgrd")  ?
>
> # Import SAGA output
> meuse.grid$sp_dist <- readGDAL("sp_dist.sdat")$band1
>
> # The new gap-filled grid is indentical to the input:
> spplot(meuse.grid, zcol=c("dist", "sp_dist"))
>
>
> In his script, Tomislav also specified an input mask grid:
> meuse.grid$mask <- as.integer(ifelse(is.na(meuse.grid$dist), NA, 1)) # or
> !isna() ?
> writeGDAL(meuse.grid["mask"], "mask.sdat", "SAGA")
> rsaga.geoprocessor(lib="grid_tools", module=7,
> param=list(INPUT="dist.sgrd",
> MASK="mask.sgrd",  RESULT="sp_dist.sgrd"))
>
> I tried to mask either the is.na() and !is.na() pixels, but still no
> interpolation takes place.
> Any help?
>
> Thanks.
>
>  Piero
>
> --
> View this message in context:
> http://r-sig-geo.2731867.n2.nabble.com/How-to-properly-use-rsaga-close-gaps-tp7567747.html
> Sent from the R-sig-geo mailing list archive at Nabble.com.
>
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