finesse.solutions.beamtrace.BeamTraceSolution.q

BeamTraceSolution.q(node)

A convenience method for getting the non-astigmatic beam parameter at a node.

Warning

This is only intended to be used on nodes which do not exhibit astigmatism. If qx != qy at the node then this method will raise a ValueError.

To get both qx and qy at a node use either:

qx, qy = trace[node]

or:

qx, qy = trace.get(node)

where trace is an instance of this class.

Parameters

nodeOpticalNode

The node at which to obtain q.

Returns

qBeamParam

The beam parameter (which is the same in both planes) at the node.

Raises

exValueError

If the beam parameters qx != qy at the node.