pyDiffMap (Python Diffusion Maps Library)
jmbr/diffusion-maps (Python Diffusion Maps Library)
dbMAP (Diffusion-Based Manifold Approximation and Projection)
scikit-learn Manifold Learning (including Laplacian Eigenmaps)
Laplacian Eigenmaps (multicore)
umap-learn (Python)
DREiMac (Dimensionality Reduction with Eilenberg-MacLane Coordinates)
Fast Approximate Nearest-Neighbor Software Libraries
flann (Fast Library for Approximate Nearest-Neighbors)
nmslib (Non-Metric-Space Library - similarity search)