make.3Dgrid: Methods to prepare 3D prediction locations

In GSIF: Global Soil Information Facilities

Description

Generates a list of objects of type "SpatialPixelsDataFrame" with longitude, latitude and altitude coordinates (these names are used by default for compatibility with the geosamples-class).

Usage

## S4 method for signature 'SpatialPixelsDataFrame'
make.3Dgrid(obj, 
      proj4s = get("ref_CRS", envir = GSIF.opts), 
      pixsize = get("cellsize", envir = GSIF.opts)[2], 
      resampling_method = "bilinear", 
      NAflag = get("NAflag", envir = GSIF.opts), 
      stdepths = get("stdepths", envir = GSIF.opts), 
      tmp.file = TRUE, show.output.on.console = TRUE, ...)
## S4 method for signature 'RasterBrick'
make.3Dgrid(obj, 
      proj4s = get("ref_CRS", envir = GSIF.opts), 
      pixsize = get("cellsize", envir = GSIF.opts)[2], 
      resampling_method = "bilinear", 
      NAflag = get("NAflag", envir = GSIF.opts), 
      stdepths = get("stdepths", envir = GSIF.opts), 
      tmp.file = TRUE, show.output.on.console = TRUE, ...)

Arguments

obj	object of class "SpatialPixelsDataFrame" or "RasterBrick"
proj4s	character; proj4string describing the target coordinate system
pixsize	grid cell size in decimal degrees (set by default at 1/1200 (0.0008333333 or 100 m around equator)
resampling_method	character; resampling method to be passed the reprojection algorithm
NAflag	character; missing value flag
stdepths	numeric; list of standard depths
tmp.file	logical; specifies whether a temporary file name should be generated
show.output.on.console	logical; specifies whether to print out the progress
...	optional arguments that can be passed to the reprojetion algorithm

Value

The output is list of objects of class "SpatialPixelsDataFrame" where the number of elements in the list corresponds to the number of standard depths.

Note

If the input object is of class "SpatialPixelsDataFrame", the method by default uses FWTools (warp command) to resample grids, otherwise the raster::projectRaster command is passed. FWTools must be installed separately.
Note: this operation can be time consuming for large areas (e.g. >> 1e6 pixels).

Author(s)

Tomislav Hengl

References

• Bivand, R.S., Pebesma, E.J., and G?mez-Rubio, V., (2008) Applied Spatial Data Analysis with R. Springer, 378 p.

• FWTools (http://fwtools.maptools.org)

• gdalUtils package (https://CRAN.R-project.org/package=gdalUtils)

• Raster package (https://CRAN.R-project.org/package=raster)

See Also

spc, geosamples-class, plotKML::reproject

Examples

## grids Ebergotzen:
library(plotKML)
library(rgdal)
library(raster)

data(eberg_grid)
gridded(eberg_grid) <- ~x+y
proj4string(eberg_grid) <- CRS("+init=epsg:31467")
##  convert to spatial components:
formulaString <- ~ PRMGEO6+DEMSRT6+TWISRT6+TIRAST6
eberg_spc <- spc(eberg_grid, formulaString)
## create 3D locations in the original coordinate system:
eberg_3Dxy <- sp3D(eberg_spc@predicted)
## Not run: ## wrapper function to create 3D locations in the default WGS84 system:
eberg_3D <- make.3Dgrid(eberg_spc@predicted)
image(eberg_3D[[1]]["PC1"])
## downscale 100 m resolution imagery to 25 m:
data(eberg_grid25)
gridded(eberg_grid25) <- ~x+y
proj4string(eberg_grid25) <- CRS("+init=epsg:31467")
eberg_grid25@data <- cbind(eberg_grid25@data, 
    warp(eberg_grid, pixsize=eberg_grid25@grid@cellsize[1], 
    GridTopology=eberg_grid25@grid, resampling_method="cubicspline")@data)
## this function requires FWTools!

## End(Not run)

GSIF documentation built on May 2, 2019, 5:44 p.m.