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calculate inverse distance weight

Source: R/utils_helper.R
inverse_distance_weight.Rd

Function for calculate inverse distance weight.

Usage

inverse_distance_weight(locx, locy, power = 1, is_arc = FALSE)

Arguments

locx

The x axis location.

locy

The y axis location.

power

(optional) Default is 1. Set to 2 for gravity weights.

is_arc

(optional) FALSE (default) or TRUE, whether to compute arc distance.

Value

A inverse distance weight matrices with class of matrix.

Details

The inverse distance weight formula is \(w_{ij} = 1 / d_{ij}^\alpha\)

Author

Wenbo Lv lyu.geosocial@gmail.com

Examples

x = 1:10
y = 1:10
inverse_distance_weight(x,y)
#>             1          2         3         4         5         6         7
#> 1  0.00000000 0.70710678 0.3535534 0.2357023 0.1767767 0.1414214 0.1178511
#> 2  0.70710678 0.00000000 0.7071068 0.3535534 0.2357023 0.1767767 0.1414214
#> 3  0.35355339 0.70710678 0.0000000 0.7071068 0.3535534 0.2357023 0.1767767
#> 4  0.23570226 0.35355339 0.7071068 0.0000000 0.7071068 0.3535534 0.2357023
#> 5  0.17677670 0.23570226 0.3535534 0.7071068 0.0000000 0.7071068 0.3535534
#> 6  0.14142136 0.17677670 0.2357023 0.3535534 0.7071068 0.0000000 0.7071068
#> 7  0.11785113 0.14142136 0.1767767 0.2357023 0.3535534 0.7071068 0.0000000
#> 8  0.10101525 0.11785113 0.1414214 0.1767767 0.2357023 0.3535534 0.7071068
#> 9  0.08838835 0.10101525 0.1178511 0.1414214 0.1767767 0.2357023 0.3535534
#> 10 0.07856742 0.08838835 0.1010153 0.1178511 0.1414214 0.1767767 0.2357023
#>            8          9         10
#> 1  0.1010153 0.08838835 0.07856742
#> 2  0.1178511 0.10101525 0.08838835
#> 3  0.1414214 0.11785113 0.10101525
#> 4  0.1767767 0.14142136 0.11785113
#> 5  0.2357023 0.17677670 0.14142136
#> 6  0.3535534 0.23570226 0.17677670
#> 7  0.7071068 0.35355339 0.23570226
#> 8  0.0000000 0.70710678 0.35355339
#> 9  0.7071068 0.00000000 0.70710678
#> 10 0.3535534 0.70710678 0.00000000
inverse_distance_weight(x,y,is_arc = TRUE)
#>               1            2            3            4            5
#> 1  0.000000e+00 6.374455e-06 3.187704e-06 2.125559e-06 1.594567e-06
#> 2  6.374455e-06 0.000000e+00 6.376358e-06 3.188893e-06 2.126512e-06
#> 3  3.187704e-06 6.376358e-06 0.000000e+00 6.379213e-06 3.190559e-06
#> 4  2.125559e-06 3.188893e-06 6.379213e-06 0.000000e+00 6.383020e-06
#> 5  1.594567e-06 2.126512e-06 3.190559e-06 6.383020e-06 0.000000e+00
#> 6  1.276036e-06 1.595401e-06 2.127782e-06 3.192702e-06 6.387781e-06
#> 7  1.063735e-06 1.276799e-06 1.596473e-06 2.129370e-06 3.195321e-06
#> 8  9.121387e-07 1.064452e-06 1.277753e-06 1.597785e-06 2.131276e-06
#> 9  7.984820e-07 9.128220e-07 1.065328e-06 1.278899e-06 1.599335e-06
#> 10 7.101191e-07 7.991407e-07 9.136421e-07 1.066363e-06 1.280236e-06
#>               6            7            8            9           10
#> 1  1.276036e-06 1.063735e-06 9.121387e-07 7.984820e-07 7.101191e-07
#> 2  1.595401e-06 1.276799e-06 1.064452e-06 9.128220e-07 7.991407e-07
#> 3  2.127782e-06 1.596473e-06 1.277753e-06 1.065328e-06 9.136421e-07
#> 4  3.192702e-06 2.129370e-06 1.597785e-06 1.278899e-06 1.066363e-06
#> 5  6.387781e-06 3.195321e-06 2.131276e-06 1.599335e-06 1.280236e-06
#> 6  0.000000e+00 6.393494e-06 3.198417e-06 2.133500e-06 1.601124e-06
#> 7  6.393494e-06 0.000000e+00 6.400162e-06 3.201991e-06 2.136043e-06
#> 8  3.198417e-06 6.400162e-06 0.000000e+00 6.407785e-06 3.206043e-06
#> 9  2.133500e-06 3.201991e-06 6.407785e-06 0.000000e+00 6.416364e-06
#> 10 1.601124e-06 2.136043e-06 3.206043e-06 6.416364e-06 0.000000e+00