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Create a kernel weights by specifying a bandwidth and a kernel method

Usage

st_kernel_weights(
  sfj,
  kernel = "gaussian",
  bandwidth = NULL,
  power = 1,
  use_kernel_diagonals = FALSE,
  is_inverse = FALSE,
  unit = "km"
)

Arguments

sfj

An sf (simple feature) object.

kernel

(optional) A string value, which has to be one of 'triangular', 'uniform', 'epanechnikov', 'quartic', 'gaussian'(default).

bandwidth

(optional) A positive numeric value of bandwidth.

power

(optional) The power (or exponent) of a number indicates how many times to use the number in a multiplication.Default is 1.

use_kernel_diagonals

(optional) FALSE (default) or TRUE, apply kernel on the diagonal of weights matrix.

is_inverse

(optional) FALSE (default) or TRUE, apply inverse on distance value.

unit

(optional) The unit for calculating spatial distance, can be 'km'(default) or 'mile'.

Value

An instance of rgeoda Weight-class.

Author

Wenbo Lv lyu.geosocial@gmail.com

Examples

guerry_path = system.file("extdata", "Guerry.shp", package = "rgeoda")
guerry = sf::read_sf(guerry_path)
st_kernel_weights(guerry)
#> Reference class object of class "Weight"
#> Field "gda_w":
#> An object of class "p_GeoDaWeight"
#> Slot "pointer":
#> <pointer: 0x55c28b7b6a70>
#> 
#> Field "is_symmetric":
#> [1] FALSE
#> Field "sparsity":
#> [1] 0.04346021
#> Field "min_neighbors":
#> [1] 1
#> Field "max_neighbors":
#> [1] 7
#> Field "num_obs":
#> [1] 85
#> Field "mean_neighbors":
#> [1] 3.694118
#> Field "median_neighbors":
#> [1] 4
#> Field "has_isolates":
#> [1] FALSE