STAG is an open-source C++ and Python library for efficient spectral graph algorithms which I am developing with He Sun. The project is under active development and the project website will be kept up to date with the latest status. To get started with using STAG, see the documentation.
The technical report includes a user guide and some example applications.
The STAG library provides an easy-to-use implementation of the ACL local graph clustering algorithm. In our paper "Local Algorithms for Finding Densely Connected Clusters", we introduce a variant of the ACL algorithm which finds clusters in a graph with many edges between them.
Spectral clustering is a popular technique for image segmentation. In our paper "A Tighter Analysis of Spectral Clustering, and Beyond", we discovered that using fewer eigenvectors for image segmentation with spectral clustering often gives better results. The python script available on GitHub gives a high-level API for image segmentation with spectral clustering.
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