## ----include = FALSE----------------------------------------------------------
knitr::opts_chunk$set(
collapse = TRUE,
comment = "#>"
)
## ----out.width = "46%", out.height = "30%", fig.show = "hold", fig.align = "center", fig.cap = "Figure 1: Contiguity", echo = FALSE----
knitr::include_graphics("Figure_1a.png")
knitr::include_graphics("Figure_1b.png")
## ----out.width = "46%", fig.show = "hold", fig.align = "center", fig.cap = "Figure 2: Edge Weights", echo = FALSE----
knitr::include_graphics("Figure_2.png")
## ----eval = FALSE-------------------------------------------------------------
# set.seed(3L)
# input_grid <- terra::rast(crs = "epsg:4326", resolution = 2, vals = sample(c(1L, NA_integer_), 16200L,
# TRUE, c(0.8, 0.2)))
# origin_pts <- rnd_locations(3L, output_type = "SpatVector")
# destination_pts <- rnd_locations(3L, output_type = "SpatVector")
#
# shortest_paths(input_grid, origin_pts)
#
# origins destinations distances
# <int> <int> <num>
# 1: 1 2 19627694
# 2: 1 3 7290325
# 3: 2 3 14467797
#
# shortest_paths(input_grid, origin_pts, destination_pts)
#
# origins destinations distances
# <int> <int> <num>
# 1: 1 1 13313293
# 2: 1 2 6158046
# 3: 1 3 15837664
# 4: 2 1 9137621
# 5: 2 2 16130624
# 6: 2 3 4810903
# 7: 3 1 15919393
# 8: 3 2 10787554
# 9: 3 3 19275995
## ----eval = FALSE-------------------------------------------------------------
# shortest_paths(input_grid, origin_pts, output = "lines")
#
# class : SpatVector
# geometry : lines
# dimensions : 3, 3 (geometries, attributes)
# extent : -179, 179, -63, -1 (xmin, xmax, ymin, ymax)
# coord. ref. : lon/lat WGS 84 (EPSG:4326)
# names : origins destinations connected
# type : <int> <int> <logical>
# values : 1 2 TRUE
# 1 3 TRUE
# 2 3 TRUE
#
# shortest_paths(input_grid, origin_pts, output = "both")
#
# class : SpatVector
# geometry : lines
# dimensions : 3, 3 (geometries, attributes)
# extent : -179, 179, -63, -1 (xmin, xmax, ymin, ymax)
# coord. ref. : lon/lat WGS 84 (EPSG:4326)
# names : origins destinations distances
# type : <int> <int> <num>
# values : 1 2 1.963e+07
# 1 3 7.29e+06
# 2 3 1.447e+07
## ----eval = FALSE-------------------------------------------------------------
# shortest_paths(input_grid, origin_pts)
#
# origins destinations distances
# <int> <int> <num>
# 1: 1 2 19627694
# 2: 1 3 7290325
# 3: 2 3 14467797
#
# shortest_paths(input_grid, origin_pts, bidirectional = TRUE)
#
# origins destinations distances
# <int> <int> <num>
# 1: 1 2 19627694
# 2: 1 3 7290325
# 3: 2 3 14467797
# 4: 2 1 19627694
# 5: 3 1 7290325
# 6: 3 2 14467797
## ----eval = FALSE-------------------------------------------------------------
# shortest_paths(input_grid, origin_pts, destination_pts, pairwise = TRUE)
#
# origins destinations distances
# <int> <int> <num>
# 1: 2 2 16130624
# 2: 1 1 13313293
# 3: 3 3 19275995
## ----eval = FALSE-------------------------------------------------------------
# origin_pts$name <- letters[1:3]
# shortest_paths(input_grid, origin_pts, origin_names = "name")
#
# origins destinations distances
# <char> <char> <num>
# 1: a b 19627694
# 2: a c 7290325
# 3: b c 14467797
## ----eval = FALSE-------------------------------------------------------------
# shortest_paths(input_grid, origin_pts, output_class = "data.frame")
#
# origins destinations distances
# 1 1 2 19627694
# 2 1 3 7290325
# 3 2 3 14467797
## ----eval = FALSE-------------------------------------------------------------
# barrier <- terra::vect("POLYGON ((-179 -25, 100 -25, 100 -26, -179 -26, -179 -25))", crs = "epsg:4326")
# shortest_paths(input_grid, origin_pts, update_rst = barrier)
#
# origins destinations distances layer
# <int> <int> <num> <int>
# 1: 1 2 19627694 0
# 2: 1 3 7290325 0
# 3: 2 3 14467797 0
# 4: 1 2 19627694 1
# 5: 1 3 13207350 1
# 6: 2 3 15465933 1
#
# barriers <- list(barrier, terra::vect("POLYGON ((0 20, 1 20, 1 -20, 0 -20, 0 20))", crs = "epsg:4326"))
# shortest_paths(input_grid, origin_pts, update_rst = barriers)
#
# origins destinations distances layer
# <int> <int> <num> <int>
# 1: 1 2 19627694 0
# 2: 1 3 7290325 0
# 3: 2 3 14467797 0
# 4: 1 2 19627694 1
# 5: 1 3 13207350 1
# 6: 2 3 15465933 1
# 7: 1 2 19813077 2
# 8: 1 3 7290325 2
# 9: 2 3 14467797 2
## ----eval = FALSE-------------------------------------------------------------
# set.seed(3L)
# input_grid <- matrix(sample(c(1L, NA_integer_), 16200L, TRUE, c(0.8, 0.2)), nrow = 90)
## ----eval = FALSE-------------------------------------------------------------
# set.seed(3L)
# origin_pts <- rnd_locations(3L)
#
# shortest_paths(input_grid, origin_pts, spherical = TRUE, radius = 3389500, extent = c(-180, 180, -90, 90))
#
# origins destinations distances
# <int> <int> <num>
# 1: 1 2 8229741
# 2: 1 3 5372309
# 3: 2 3 9088755
## ----eval = FALSE-------------------------------------------------------------
# set.seed(3L)
# input_grid <- list(even_terrain = input_grid, temperature = matrix(stats::rnorm(16200L, 20, 5), nrow = 90))
# custom_tr <- function(v1, v2) v1[[1L]] * v2[[1L]] + v1[[2L]] * v2[[2L]]
# custom_tr <- function(v1, v2) v1[["even_terrain"]] * v2[["even_terrain"]] + v1[["temperature"]] * v2[["temperature"]]
#
# shortest_paths(input_grid, origin_pts, spherical = TRUE, radius = 3389500, extent = c(-180, 180, -90, 90), tr_fun = custom_tr)
#
# origins destinations distances
# <int> <int> <num>
# 1: 1 2 15973.37
# 2: 1 3 10254.19
# 3: 2 1 15973.37
# 4: 2 3 17432.90
# 5: 3 1 10254.19
# 6: 3 2 Inf
## ----eval = FALSE-------------------------------------------------------------
# set.seed(3L)
# input_grid <- matrix(sample(c(1L, NA_integer_), 16200L, TRUE, c(0.8, 0.2)), nrow = 90)
#
# barrier_vector <- sample.int(16200L, 10L)
# shortest_paths(input_grid, origin_pts, spherical = TRUE, radius = 3389500, extent = c(-180, 180, -90, 90), update_rst = barrier_vector)
#
# origins destinations distances layer
# <int> <int> <num> <int>
# 1: 1 2 8229741 0
# 2: 1 3 5372309 0
# 3: 2 3 9088755 0
# 4: 1 2 8229741 1
# 5: 1 3 5372309 1
# 6: 2 3 9088755 1
#
# barrier_matrix <- matrix(rep.int(1L, 16200L), nrow = 90)
# barrier_matrix[sample.int(16200L, 10L)] <- NA_integer_
# shortest_paths(input_grid, origin_pts, spherical = TRUE, radius = 3389500, extent = c(-180, 180, -90, 90), update_rst = barrier_matrix)
#
# origins destinations distances layer
# <int> <int> <num> <int>
# 1: 1 2 8229741 0
# 2: 1 3 5372309 0
# 3: 2 3 9088755 0
# 4: 1 2 8229741 1
# 5: 1 3 5372309 1
# 6: 2 3 9088755 1
## ----eval = FALSE-------------------------------------------------------------
# shortest_paths(input_grid, origin_pts, show_progress = TRUE)
#
# Checking arguments
# Converting spatial inputs
# Preparing algoritm inputs
# Starting distances calculation
# |---|
# |===|
# Generating output object
# origins destinations distances
# <int> <int> <num>
# 1: 1 2 19627694
# 2: 1 3 7290325
# 3: 2 3 14467797