Helps in thinning points either in geographic or environmental space
Source:R/selection_helpers.R
point_thinning.Rd
Point thinning based on user-defined distances in geographic or environmental space.
Usage
point_thinning(data, x_column, y_column, thinning_distance, space,
max_n_samples = 1, replicates = 10, set_seed = 1)
Arguments
- data
matrix or data.frame that contains at least two columns.
- x_column
(character) the name of the x-axis.
- y_column
(character) the name of the y-axis.
- thinning_distance
(numeric) distance for thinning. Units must be selected according to the space, kilometers (km) for geographic and Euclidean distances for environmental space.
- space
(character) space in which the thinning will be performed. There are two options available: "G", if it will be in geographic space, and "E", if it will be in environmental space.
- max_n_samples
(numeric) maximum number of samples to chose with most points included. Default = 1.
- replicates
(numeric) number of thinning replicates. Default = 10.
- set_seed
(numeric) integer value to specify a initial seed. Default = 1.
Value
A list with one or more elements, depending on max_n_samples
. Each
element is a data.frame containing points retained after thinning. All
elements are different in at least one of the selected points.
Examples
# Data
m_matrix <- read_master(system.file("extdata/m_matrix.rds",
package = "biosurvey"))
data1 <- m_matrix$data_matrix
# Thinning the points
thin <- point_thinning(data1, x_column = "Longitude", y_column = "Latitude",
thinning_distance = 200, space = "G",
max_n_samples = 1, replicates = 5, set_seed = 1)