coflandscaper.default_shift_from_cif¶

coflandscaper.default_shift_from_cif(input_file, topo, print_shift=False)[source]¶

Compute the default slip length and angle for AB stacking.

For both hcb and kgm, the default AB shift length uses (2/sqrt(3)) * ||0.5*(a+b)|| and the angle is fixed to 90°.

Parameters:

input_file (str) – Path to the CIF file.
topo (str) – Topology string. Allowed values are “sql”, “hcb”, or “kgm”.
print_shift (bool) – If True, print computed default shift values. Defaults to False.

Returns:

(length, angle_deg) tuple.

Raises:

ValueError – If topo is not “sql”, “hcb”, or “kgm”.

Return type:

tuple[float, float]