make.blocksraster {DEPONS2R}

Makes new file with blocks

Description

Produces a DeponsRaster object of type='blocks' for use in DEPONS simulations. This allows animals to be counted within specific regions (blocks) of the landscape during the simulation. The new blocks can be specified as either matrices or SpatialPolygons objects. For matrices, the blocks are defined as the smallest rectangle that includes all the specified positions.

Usage

## S4 method for signature 'DeponsRaster'
make.blocksraster(
  template,
  blocks = NA,
  blockvals = NULL,
  NAvalue = -9999,
  plot = FALSE,
  fname = NULL,
  overwrite = FALSE
)

Arguments

template

DeponsRaster object used as template for new blocks file

blocks

list of areas to be used for new blocks. Each item in 'blocks' should be a matrix (with two columns, corresponding to x- and y-coordinates) or a SpatialPolygons object

blockvals

Vector of integer values defining the labels of the new blocks. The first value defines the background value, so the length of 'blockvals' should equal the number of blocks plus 1

NAvalue

Value used for missing data in the output object

plot

If TRUE, the raster block is plotted

fname

Name of the output raster file (character string ending with '.asc'). No file is written to disk if fname is not provided.

overwrite

Whether to replace existing file.

Value

RasterLayer object defining different subregions of the landscape where animals should be counted.

Note

The blocks file should not be modified when running DEPONS simulations using the 'Kattegat' landscape. In this landscape the simulated animals use the blocks file for navigation. Also note that blocks are added to the new blocks raster in the order they are file in the order in which they are listed in 'blocks', so the order mattes if the blocks overlap.

Examples

#Load file to use as template for new blocks file
data("bathymetry")

# Make list of blocks to create
new.blocks <- list()
x <- runif(8, 700000, 760000)
y <- runif(8, 6200000, 6300000)
new.blocks[[1]] <- cbind(x,y)
x <- c(600000, 635000, 670000, 635000)
y <- c(6150000, 6200000, 6150000, 6100000)
library(sp)
srl <- list(Polygon(cbind(x,y)))
Srl <- list(Polygons(srl, ID=as.vector("p")))
new.blocks[[2]] <- SpatialPolygons(Srl, proj4string=crs(bathymetry))

make.blocksraster(bathymetry, new.blocks, plot=TRUE)
points(new.blocks[[1]])
plot(new.blocks[[2]], add=TRUE)


the.dir <- tempdir()
make.blocksraster(bathymetry, new.blocks, fname=paste0(the.dir, "/test.asc"))