I want to delete all of the outliers I got from DBSCAN clustering, which are labelled -1.

How do I delete outliers I got from DBSCAN clustering?

Answer 1

[Sharad]

Hi,

As per my understanding, you are interested in deleting all the outliers obtained from DBSCAN clustering in MATLAB.

In order to do this, you can follow these steps:

• The MATLAB dbscan function returns an array idx, containing the value that represents the cluster (cluster label) for each index or point in the input dataset.

idx = dbscan(X,epsilon,minpts)

• The points which are outliers may be represented by -1 label, and you can easily locate those with the find() function.

outlierIndices = find(idx == -1);

• Finally you can remove the outliers in the dataset like this.

newData = dataset;
newData(outlierIndices, :) = [];

Here are some documentation links that you might want to follow:

DBSCAN : https://in.mathworks.com/help/stats/dbscan-clustering.html

find() : https://in.mathworks.com/help/matlab/ref/find.html

Thank you.