Map a raster stack of a list of rasters

Map stratified rasters to a combined stratification.

Usage

strat_map(
  sraster,
  stack = FALSE,
  filename = NULL,
  overwrite = FALSE,
  plot = FALSE,
  details = FALSE
)

Arguments

sraster: spatRaster or list. Stratification raster stack or list of rasters. If sraster is of class list, then it is internally converted into a raster stack.
stack: Logical. Default = FALSE. If TRUE, inputs and output will be stacked: strata_1, strata_2, ..., strata.
filename: Character. Path to write stratified raster to disc.
overwrite: Logical. Specify whether filename should be overwritten on disc.
plot: Logical. Plots output strata raster and visualized strata with boundary dividers.
details: Logical. If FALSE (default) output is a mapped stratified spatRaster object. If TRUE return a list where $outRaster is the mapped stratified raster, and $lookUp is the lookup table for the stratification.

Value

A spatRaster object.

Mapping

The mapping algorithm will take the stratification from sraster and combine it with overlying strata values across all layers. This will result in a strata attribute where the values from all inputs are combined.

i.e.

If strata_1 = 1 and strata_2 = 1 then strata = 11.

If strata_1 = 2 and strata_2 = 14 then strata = 214.

If strata_1 = "A" and strata_2 = 14 then strata = "A14".

Author

Tristan R.H. Goodbody, Tommaso Trotto, Robert Hijmans

Examples

#--- load input metrics rasters ---#
raster <- system.file("extdata", "sraster.tif", package = "sgsR")
sraster <- terra::rast(raster)

#--- read polygon coverage ---#
poly <- system.file("extdata", "inventory_polygons.shp", package = "sgsR")
fri <- sf::st_read(poly)
#> Reading layer `inventory_polygons' from data source 
#>   `/home/runner/work/_temp/Library/sgsR/extdata/inventory_polygons.shp' 
#>   using driver `ESRI Shapefile'
#> Simple feature collection with 632 features and 3 fields
#> Geometry type: MULTIPOLYGON
#> Dimension:     XY
#> Bounding box:  xmin: 431100 ymin: 5337700 xmax: 438560 ymax: 5343240
#> Projected CRS: UTM_Zone_17_Northern_Hemisphere

#--- stratify polygon coverage ---#
#--- specify polygon attribute to stratify ---#

attribute <- "NUTRIENTS"

#--- specify features within attribute & how they should be grouped ---#
#--- as a single vector ---#

features <- c("poor", "rich", "medium")

srasterfri <- strat_poly(
  poly = fri,
  attribute = attribute,
  features = features,
  raster = sraster
)

#--- map srasters with raster stack ---#
stack <- c(srasterfri, sraster)
strat_map(
  sraster = stack
)
#> class       : SpatRaster 
#> size        : 277, 373, 1  (nrow, ncol, nlyr)
#> resolution  : 20, 20  (x, y)
#> extent      : 431100, 438560, 5337700, 5343240  (xmin, xmax, ymin, ymax)
#> coord. ref. : UTM Zone 17, Northern Hemisphere 
#> source(s)   : memory
#> varname     : sraster 
#> name        : strata 
#> min value   :     11 
#> max value   :     34 

#--- map sraster with list of rasters ---#
rast_list <- list(srasterfri, sraster)
strat_map(
  sraster = rast_list,
  stack = TRUE,
  details = TRUE
)
#> Stacking srasters and their combination (strata).
#> $raster
#> class       : SpatRaster 
#> size        : 277, 373, 3  (nrow, ncol, nlyr)
#> resolution  : 20, 20  (x, y)
#> extent      : 431100, 438560, 5337700, 5343240  (xmin, xmax, ymin, ymax)
#> coord. ref. : UTM Zone 17, Northern Hemisphere 
#> sources     : memory  
#>               sraster.tif  
#>               memory  
#> varnames    : sraster 
#>               sraster 
#>               sraster 
#> names       : strata_1, strata_2, strata 
#> min values  :        1,        1,     11 
#> max values  :        3,        4,     34 
#> 
#> $lookUp
#>    strata_1 strata_2 strata
#> 1         1        1     11
#> 2         1        2     12
#> 3         1        3     13
#> 4         1        4     14
#> 5         2        1     21
#> 6         2        2     22
#> 7         2        3     23
#> 8         2        4     24
#> 9         3        1     31
#> 10        3        2     32
#> 11        3        3     33
#> 12        3        4     34
#>