This code is a C++ implementation of the HOTRG algorithm based on the article:
Coarse-graining renormalization by higher-order singular value decomposition Phys. Rev. B 86, 045139 (2012), http://arxiv.org/abs/1201.1144v4
For linear algebra (Singular Value Decomposition (SVD) in particular), Eigen library (3.2.7) is called.
This code is parallelized by OpenMP.
Compilation under Mac:
g++ -m64 -O3 -fopenmp -I/.../Eigen main.cpp -o main.x