Welcome to the Systems Engineering Library (se-lib) (previously called PyML). It provides capabilities for integrated systems modeling, simulation, analysis and diagrams covering SysML, discrete event and continuous system dynamics simulation, reliability analysis, causal analysis, project management, and more using simple Python code as the glue.

The open source Python scientific computing ecosystem enables advanced analysis with powerful libraries and language features. se-lib is built with Graphviz, Matplotlib, NetworkX, NumPy and SciPy integrated with Python for all systems modeling.

New Online Capability and Simulation

The upcoming se-lib v.3 can run online in a browser. Try it at the SysML Diagram Scratchpad or the Discrete Event Modeling Demonstrations. We have also added causal loop modeling (causal diagrams) and system dynamics modeling and simulation capabilities.

Inputs and Outputs

The diagram below shows the primary inputs and outputs of se-lib, and was generated with se-lib utilities.


Current Features

This current features of se-lib can be found under Function Reference.


The following was presented at the 2022 INCOSE San Diego Mini-Conference.


se-lib research and development is supported by these sponsors:


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