finesse.components.node module

Objects for connecting and registering connections between components.

class finesse.components.node.ElectricalPort(name: str, component, node_type: NodeType = NodeType.ELECTRICAL, input: bool = True, input_unit: str = 'W', output: bool = True, output_unit: str = 'W')[source]: Bases: Port

class finesse.components.node.MechanicalPort(name, component, node_type=NodeType.MECHANICAL)[source]: Bases: Port

class finesse.components.node.Node(name, port, node_type, direction, unit: str)[source]

Bases: object

Represents a specific connection at a component.

Mathematically a node represents a single equation in the interferometer matrix.

A node can only be owned by a single component instance - with weak references stored by the connected components.

Parameters

namestr: Name of newly created node.
componentPort: The port that this node belongs to.
node_typeNodeType: Physical node type.

property component: ModelElement[source]

The component which has ownership of this node.

Getter:: Returns the component that this node belongs to (read-only).

property connections[source]

Connections of this node.

Getter:: Returns a collection of Space, Wire, or DegreeOfFreedom objects attached to this node (read-only).

property direction[source]

NodeDirection of this node.

This is largely a description to help understand how external information flow in and out of a component. Inside a component all nodes will couple to one another in more complex ways.

Input nodes are those going into a component, whereas output describe those leaving. For example incident and reflected light fields.

Bidrectional takes information either direction. For example a mechanical degree of freedom, external forces can be applied to it, or its motion can be coupled to some external system.

Getter:: Returns the directionality of the node (read-only).

property full_name[source]

Full name.

Getter:: Returns a full name of the node: {component name}.{port name}.{node name}

property is_input[source]

Flag indicating whether this node is an input to the associated component.

Getter:: Returns True if the field at this node goes into self.component (read-only).

is_neighbour(node)[source]

Checks if node is a connected by an edge to this node.

Parameters

nodeNode: Node with which to check connection.

Returns

flagbool: True if node is connected to this node, False otherwise.

property name[source]

Name of the node object.

Getter:: Returns the name of the node (read-only).

property port: Port[source]

Port this node is attached to.

Getter:: Returns the port of this node (read-only).

property port_name[source]

Port name.

Getter:: Returns a shortened name of the node: {port name}.{node name}

property tag[source]

Tagged name of the node object.

Getter:: Returns the tagged (user-defined) name of the node (read-only).

property type[source]

NodeType of the node object.

Getter:: Returns the node-type of the node (read-only).

property unit[source]

class finesse.components.node.NodeDirection(*values)[source]

Bases: Enum

Enum describing the direction that information at a Node flows.

This is largely a description to help understand how external information flows in and out of a component. Inside a component all nodes will couple to one another in more complex ways.

Input nodes are those going into a component, whereas output describe those leaving. For example incident and reflected light fields.

Bidrectional takes information either direction. For example a mechanical degree of freedom, external forces can be applied to it, or its motion can be coupled to some external system.

BIDIRECTIONAL = 2

INPUT = 0

OUTPUT = 1

class finesse.components.node.NodeType(*values)[source]

Bases: Enum

Enum describing the physical connection type of a Node

ELECTRICAL = 1

MECHANICAL = 2

OPTICAL = 0

class finesse.components.node.OpticalNode(name, port, direction, unit: str = 'sqrt(W)')[source]

Bases: Node

Represents a specific optical port connection at a component.

OpticalNodes also have additional physical properties such as the beam parameter (of type BeamParam) at the nodes’ position within the interferometer.

Parameters

namestr: Name of the optical node.
portPort: The port that this node belongs to.
directionNodeDirection: True if the field at this node is going into the component.

static get_opposite_direction(node)[source]

Returns the opposite direction of a node from either a Node object or a full string name qualifier for a node, component.port.direction l1.p1.o.

Parameters

node[str | Node]: Node to invert

property opposite[source]

The opposite direction node.

Getter:: Returns the opposite direction node to this one.

property q[source]

Beam parameter value at this node.

Getter:: Returns the beam parameter at this node. If the beam parameters in the tangential and sagittal planes are different then it returns a tuple of the two parameters.
Setter:: Sets the beam parameter at this node. If the argument provided is a 2-tuple then the parameter is set astigmatically for the node.

property qx[source]

Beam parameter value in the tangential plane.

Getter:: Returns the beam parameter at the node in the tangential plane.
Setter:: Sets the beam parameter at the node in the tangential plane.

property qy[source]

Beam parameter value in the sagittal plane.

Getter:: Returns the beam parameter at the node in the sagittal plane.
Setter:: Sets the beam parameter at the node in the sagittal plane.

property space[source]

A reference to the Space object attached to this node.

Getter:: Returns a reference to the Space object attached to the node (read-only).

class finesse.components.node.OpticalPort(name: str, component, node_type: NodeType = NodeType.OPTICAL, input: bool = True, output: bool = True)[source]: Bases: Port

class finesse.components.node.Port(name, component, node_type)[source]

Bases: Freezable

A collection of all the nodes at a specific point/surface of a component.

Parameters

namestr: Name of newly created node.
componentSub-class of Connector: The component that this node belongs to.
node_typeNodeType: Physical node type.

property attached_to[source]

Components that this port is attached to. Optical ports are only ever connected to Space elements. Ports containing signal nodes can have multiple connections and returns a Set.

Getter:: Returns the component this port is attached to, or returns None if no such connected component exists. Signal ports return a Set of components attached (read-only).

property component: ModelElement[source]

The component which has ownership of this port.

Getter:: Returns the component that this port belongs to (read-only).

property enabled[source]

property full_name: str[source]

Getter:: Returns a full name of the port: {component name}.{port name}

get_unique_node(predicate: Callable[[Node], bool])[source]

Returns the unique node at this port that satisfies the provided predicate. If multiple nodes satisfy this predicate then a RuntimeError is raised.

Parameters

predicateCallable[[Node], bool]: A callable that accepts a Node and returns a boolean value

Examples

Selecting a unique output node:: port.get_unique_node(lambda node: not node.is_input)

property is_connected[source]

Flag indicating whether the port is attached to another component.

Getter:: Returns true if this port is attached to another component (read-only).

mechanical_connection: MechanicalConnector | None

property name[source]

Name of the port object.

Getter:: Returns the name of the port (read-only).

node(name)[source]: Get a node at this port by its name.

property nodes: tuple[Node, ...][source]

Nodes associated with the port.

Getter:: Returns a tuple of the associated nodes at this port (read-only).

property refractive_index[source]

If the port is an Optical port, this will return a symbolic value for the refractive index at this port. The refractive index is set by the Space elements that are attached to it.

Returns

nrSymbol: Symbolic value for refractive index

property space[source]

Space that the port is attached to. Equivalent to Port.attached_to.

Getter:: Returns the space that this port is attached to (read-only).

property type[source]

NodeType of the port object.

Getter:: Returns the node-type of the port (read-only).

class finesse.components.node.SignalNode(name, port, direction, node_type, unit: str = 'n/a')[source]

Bases: Node

Represents a specific small signal degree of freedom. A signal is some small AC oscillation in some property, such as longitudinal motion, voltage, laser amplitude, etc.

Parameters

namestr: Name of the mechanical motion.
portPort: The port that this node belongs to.
num_frequenciesint: Number of mechanical frequencies to model

property frequencies[source]

property num_frequencies[source]