rdwplus (version 1.0.1)

reclassify_streams: Reclassify streams into various formats

Description

Re-format a stream raster.

Usage

reclassify_streams(stream, out, out_type = "binary", overwrite = FALSE)

Value

Nothing. A file with the name out will be written to the current GRASS mapset. This raster will be in unsigned integer format.

Arguments

stream

Name of a streams raster in the current GRASS mapset. This can be the output from rasterise_stream. The raster should have NoData values for all non-stream cells. Stream cells can have any other value.

out

The output file.

out_type

Either 'zeros_to_nodata', 'binary', 'unary', or 'none'. See Details below

overwrite

A logical indicating whether the output should be allowed to overwrite any existing files. Defaults to FALSE.

Details

Given a streams raster, this function will either create a binary streams raster (0 for non-stream cells and 1 for stream cells) or a unary streams raster (1 for stream cells and NoData for all other cells). Another option is to reclassify the streams raster such that stream cells are given the value NoData and non-stream cells are given the value 1.

Do not use raster names containing dashes/hyphens. The underlying call to r.calc will crash if the raster name contains these symbols because they are misinterpreted as math symbols.

Examples

# Will only run if GRASS is running
if(check_running()){
# Retrieve paths to data sets
dem <- system.file("extdata", "dem.tif", package = "rdwplus")
lus <- system.file("extdata", "landuse.tif", package = "rdwplus")
sts <- system.file("extdata", "site.shp", package = "rdwplus")
stm <- system.file("extdata", "streams.shp", package = "rdwplus")

# Set environment 
set_envir(dem)

# Get other data sets (stream layer, sites, land use, etc.)
raster_to_mapset(lus)
vector_to_mapset(c(stm, sts))

# Reclassify streams
out_stream <- paste0(tempdir(), "/streams.tif")
rasterise_stream("streams", out_stream, TRUE)
reclassify_streams("streams.tif", "streams01.tif", overwrite = TRUE)
}