denpoints: denpoints

Description Usage Arguments Details Value Author(s) References Examples

Description

denpoints Estimates the densities values of a sample.

Usage

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denpoints(x, k = 4)

Arguments

x

A distance matrix calculated on data or a matrix

k

The number of nearest neighbors to calculate local point density

Details

For a fixed y, density of y is defined as the sum of distance(y,z) on all z that are the k-nearest neighbors of y

Value

dpoints

A real vector containing the density values for each point

Author(s)

Juan Domingo Gonzalez <juanrst@hotmail.com>

References

Hasan AM, et al. Robust partitional clustering by outlier and density insensitive seeding. Pattern Recognition Letters, 30(11), 994-1002, 2009.

Examples

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#generate normal data in dimension 2
X=matrix(rnorm(1000),ncol=2)
a<- denpoints(x=X,k=4)


#### ten most isolated points
most_isolated=order(a)[1:10]

### plotting results: (most isolated points should be shown in green)
plot(X)
points(X[ most_isolated, ], pch=19,col=3)

ktaucenters documentation built on Aug. 3, 2019, 9:03 a.m.