API Reference

Complete reference documentation for Lynx’s Python API. All public methods, parameters, and examples are documented here.

Diagram Management

Create, save, and load diagrams. The central class for all Lynx operations.

Diagram Class

Block Library

Basic control systems blocks: gain, transfer function, state space, sum

Block Types

Validation

Diagram correctness: algebraic loops, connectivity, label uniqueness.

Validation

Python-Control Export

Export diagrams to python-control for analysis and simulation.

Python-Control Export

Quick Reference

Common tasks and their corresponding API methods:

Task	API Method	Example
Create diagram	lynx.Diagram()	diagram = lynx.Diagram()
Add block	diagram.add_block()	diagram.add_block('gain', 'K1', K=5.0)
Add connection	diagram.add_connection()	diagram.add_connection('c1', 'K1', 'out', 'plant', 'in')
Update parameter	block.set_parameter()	diagram["block_label"].set_parameter("parameter_name", new_value)
Save diagram	diagram.save()	diagram.save('my_diagram.json')
Load diagram	lynx.Diagram.load()	diagram = lynx.Diagram.load('my_diagram.json')
Export transfer function	diagram.get_tf()	sys = diagram.get_tf('r', 'y')
Export state-space	diagram.get_ss()	sys = diagram.get_ss('r', 'y')
Interactive widget	lynx.edit()	lynx.edit(diagram)

Detailed Documentation

• Diagram Class
  • Overview
  • Creating Diagrams
  • Adding Blocks
  • Adding Connections
  • Saving and Loading
  • Exporting to Python-Control
  • Interactive Widget
  • API Reference
  • See Also
• Block Types
  • Block Comparison
  • API Reference
  • See Also
• Validation
  • Validation Layers
  • Automatic Validation
  • ValidationError
  • Common Validation Errors
  • Pre-Export Validation Workflow
  • SignalNotFoundError
  • See Also
• Python-Control Export
  • Export Methods
  • See Also

API Conventions

Parameter Types

Lynx uses type hints throughout. Common parameter types:

• block_type: str - One of: 'gain', 'transfer_function', 'state_space', 'sum', 'io_marker'

• block_id: str - Unique identifier for a block

• port_id: str - Port identifier (e.g., 'in', 'out', 'in1', 'in2')

• position: dict[str, float] - {'x': float, 'y': float} coordinates

Return Values

• Methods that modify diagrams typically return None (modify in-place)

• Export methods return python-control objects: TransferFunction or StateSpace

• Load methods return new Diagram instances

Error Handling

Lynx raises descriptive exceptions with context:

• ValidationError: Pre-export validation failures (includes block_id and port_id)

• SignalNotFoundError: Signal reference not found during export

• ValueError: Invalid parameters or arguments

See Validation for details on error handling and recovery.