Conventions
In most cases, the units of the function arguments and returns are in angstrom unit for lattice, and fractional w.r.t lattice for atomic positions, etc.
The following abbreviations are used throughout the code and documentation:
n_bandsfor number of bandsn_wannfor number of WFsn_kptsfor number of kpointsn_bvecsfor number of b-vectorsn_atomsfor number of atomsAforamnmatricesMformmnmatricesEforeigmatricesSforspnmatrices
In most cases, for arrays we adopt the convention that n_bands is the first index, n_wann is the second index, and n_kpts is the third index. For example, A for the amn matrices is a 3D array of size (n_bands, n_wann, n_kpts).