`mass_center`#

biotite.structure.mass_center(array: AtomArray[N] | AtomArrayStack[M, N], masses: ndarray[tuple[N], dtype[floating]] | None = None) → ndarray[tuple[XYZ], dtype[floating]] | ndarray[tuple[M, XYZ], dtype[floating]][source]#

Calculate the center(s) of mass of an atom array or stack.

Parameters:

arrayAtomArray or AtomArrayStack: The array or stack to calculate the center(s) of mass for.
massesndarray, optional: The masses to use for each atom in the input array. Must have the same length as array. By default, the standard atomic mass for each element is taken.

Returns:

radiusndarray, ndarray, dtype=float: Array containing the the coordinates of the center of mass. If array is an AtomArray, this will be an length 3 ndarray; if it is an AtomArrayStack with n models, a (n x 3) ndarray is returned.