Uses flexsdm::sample_pseudoabs(method = c("env_const", env = predictors) within each timestamp stratum so that pseudo-absences match the temporal distribution of presences. Extracts covariate values for the sampled coordinates and returns a data.frame with the same predictor columns.
generate_pa_env_space_flexsdm(
presences,
raster_stack,
predictor_variables,
coords = c("decimalLongitude", "decimalLatitude"),
ratio = 1,
attempts = 100,
seed = NULL
)
A data frame of pseudo-absences with coordinates, timestamp, `pa = 0`, and covariate values.
Data frame containing presence points.
`SpatRaster` object containing covariate data. Uses continuous predictor only and samples per timestamp.
Character vector of the predictor variables selected for this species.
Character vector specifying the column names for latitude and longitude. Defaults to `c("decimalLongitude", "decimalLatitude")`.
Ratio of pseudo-absences to presences (default 1 = balanced).
Integer specifying the number of attempts to generate exact pseudo-absences. Defaults to 100.
Optional seed for reproducibility.