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Given a list of chemical species either as a atomic numbers or chemical symbols, return the correponding list of ordered atomic numbers with d

Used to calculate discrete vectors for the polynomial basis functions. Args: r_cut(float): Radial cutoff. n_max(int):

Elaborate test system with multiple species, non-cubic cell, and close-by atoms.

Find all points within a sphere from the point taking into account periodic boundary conditions. This includes sites in other periodi

Simple bulk system.

Returns an atomic system and SOAP parameters which are ideal for most tests.