is_alternating

is_alternating(k)

Check if a diagram is alternating.

A diagram is alternating if each edge meets consecutive endpoints of alternating parity around crossings.

Parameters:

k (PlanarDiagram | OrientedPlanarDiagram) – Planar diagram.

Returns:

True if k is alternating, False otherwise.

Return type:

bool

Example

>>> import knotpy as kp
>>> k = kp.knot("8_19")
>>> kp.is_alternating(k)
False