Using the Triangle Inequality to Accelerate TTSAS Cluster Algorithm

Two-Threshold Sequential Algorithm Scheme (TTSAS) is a straightforward clustering algorithm, and do not a priori presume a fixed number of clusters. We show how to accelerate it dramatically, while still always computing exactly the same result as the standard algorithm. The accelerated algorithm TI_TTSAS avoids unnecessary distance calculations by applying the triangle inequality. Experiments show that the new algorithm is more effective for datasets of more dimensions, and becomes more and more effective as the number of clusters increases.