getAreaStep: Calculate dBBMM and overlapping areas in steps

In YuriNiella/RSP: Refined Shortest Paths

Calculate dBBMM and overlapping areas in steps

Description

When a long study period is analysed the dBBMM can crash R since they are computationally heavy. You can use this function to calculate the dBBMMs and overlapping areas (between pairs of groups) according to a fixed step (i.e. timeframe in number of days), and export the output to disk as it goes. If your computer runs out of memory and kills R, you can then resume the calculations by setting a new output name (name.new) and specifying the previous one already stored in disk (name.file), and defining the new start date to resume the calculations (start.time). It currently only works with the 50

Usage

getAreaStep(
  input,
  base.raster,
  UTM,
  timeframe = 1,
  start.time = NULL,
  save = TRUE,
  name.new = NULL,
  name.file = NULL,
  groups = NULL
)

Arguments

input	The output of runRSP.
base.raster	The water raster of the study area. For example the output of shapeToRaster.
UTM	The UTM zone of the study area. Only relevant if a latlon-to-metric conversion is required.
timeframe	The intended temporal interval of interest (in number of days) to perform the calculations. Default is 1 day.
start.time	Character vector identifying the initial date (format = "Y-m-d") to start the calculations.
save	Logical (default is TRUE). Do you want to save the calculated areas to disk?
name.new	File name (character) to save calculations output to disk.
name.file	File name (character) of previous calculations output to be imported (if any).
groups	Vector of group names (character) of interest to perform calculations.

Value

A dataframe of dBBMM areas per group and the corresponding overlaps

Examples

# Import river shapefile
water <- actel::shapeToRaster(shape = paste0(system.file(package = "RSP"), "/River_latlon.shp"), 
size = 0.0001, buffer = 0.05) 

# Create a transition layer with 8 directions
tl <- actel::transitionLayer(x = water, directions = 8)

# Import example output from actel::explore() 
data(input.example) 

# Run RSP analysis
rsp.data <- runRSP(input = input.example, t.layer = tl, coord.x = "Longitude", coord.y = "Latitude")

# Calculate dBBMM and overlaps in steps:
df.areas <- getAreaStep(input = rsp.data, base.raster = water, UTM = 56, timeframe = 1, 
 name.new = "save.csv", groups = c("G1", "G2")) 

YuriNiella/RSP documentation built on Feb. 2, 2024, 5:03 a.m.