Merge SWD Objects

Merge two SWD objects.

Usage

mergeSWD(swd1, swd2, only_presence = FALSE)

Arguments

swd1

SWD object.

swd2

SWD object.

only_presence

logical If TRUE only for the presence locations are merged and the absence/background locations are taken only from the swd1 object.

Value

The merged SWD object.

Details

• In case the two SWD objects have different columns, only the common columns are used in the merged object.

• The SWD object is created in a way that the presence locations are always before than the absence/background locations.

Author

Sergio Vignali

Examples

# Acquire environmental variables
files <- list.files(path = file.path(system.file(package = "dismo"), "ex"),
                    pattern = "grd",
                    full.names = TRUE)

predictors <- terra::rast(files)

# Prepare presence and background locations
p_coords <- virtualSp$presence
bg_coords <- virtualSp$background

# Create SWD object
data <- prepareSWD(species = "Virtual species",
                   p = p_coords,
                   a = bg_coords,
                   env = predictors,
                   categorical = "biome")
#> ℹ Extracting predictor information for presence locations
#> ✔ Extracting predictor information for presence locations [21ms]
#> 
#> ℹ Extracting predictor information for absence/background locations
#> ✔ Extracting predictor information for absence/background locations [45ms]
#> 

# Split only presence locations in training (80%) and testing (20%) datasets
datasets <- trainValTest(data,
                         test = 0.2,
                         only_presence = TRUE)
train <- datasets[[1]]
test <- datasets[[2]]

# Merge the training and the testing datasets together
merged <- mergeSWD(train,
                   test,
                   only_presence = TRUE)

# Split presence and absence locations in training (80%) and testing (20%)
datasets
#> [[1]]
#> 
#> ── Object of class: <SWD> ──
#> 
#> ── Info 
#> • Species: Virtual species
#> • Presence locations: 320
#> • Absence locations: 5000
#> 
#> ── Variables 
#> • Continuous: "bio1", "bio12", "bio16", "bio17", "bio5", "bio6", "bio7", and
#> "bio8"
#> • Categorical: "biome"
#> 
#> [[2]]
#> 
#> ── Object of class: <SWD> ──
#> 
#> ── Info 
#> • Species: Virtual species
#> • Presence locations: 80
#> • Absence locations: 5000
#> 
#> ── Variables 
#> • Continuous: "bio1", "bio12", "bio16", "bio17", "bio5", "bio6", "bio7", and
#> "bio8"
#> • Categorical: "biome"
#> 
datasets <- trainValTest(data,
                         test = 0.2)
train <- datasets[[1]]
test <- datasets[[2]]

# Merge the training and the testing datasets together
merged <- mergeSWD(train, test)