dist.fun.tricubic: Tricubic distance functions for topological k-NN classifier
Description
The tricubic function is used as distance-dependent weight \(w\) for
k-NN voting.
Usage
dist.fun.tricubic(x, sigma = 1)
Value
Distance-dependent weight.
Arguments
- x
Distance or numeric vector or matrix of distances.
- sigma
Maximum distance to be considered.
Details
The function returns 1.0 for \(x = 0\), 0.0 for \(x \ge \sigma\) and
$$w(x) = (1 - x^3 / \sigma^3)^3$$
for \(0 < x < \sigma\).