Gallery¶
The 54 models that ship in the package, by kind. Each runs as it is.
| Page | Models |
|---|---|
| Agent-based | Boids flock (continuous, heading), Nagel-Schreckenberg traffic (ring), Schelling segregation (grid), SIR on a small-world network, Sugarscape with regrowth (grid, patches), Wolf-Sheep predation with grass (grid), Bass diffusion (agents), Machine agent with repair, Courier on a path network, Random walker (continuous space), Server busy/idle cycle (agents), SIR epidemic (agents) |
| Energy | Biogas digester, holder and CHP, Biogas plant (library assets), Depot: PV, EV charging and heat pump, PV + battery sizing and dispatch, PV + battery site (library assets) |
| Games | Emergency department: staffing game, Supply line: order-rate management game |
| Logistics | Warehouse with forklifts (floor plan), Order-driven warehouse (library assets) |
| Manufacturing | Robot cell against manual assembly, Automation floor (robot cells, AMR, palletiser), Job shop (Jackson network), Job shop (routed, per-product sequences), Line with finite buffers, Machine with breakdowns, Job shop with MES digital twin, Make-to-order line (library assets), Orders, due dates and tardiness, Priority jobs with rework, Two-cell line (reusable submodel) |
| Services | Call centre on real dates, Walk-in clinic (library assets), Walk-in clinic digital twin, Emergency department with patient agents, Impatient customers (balking and reneging) |
| Supply chain | (s, S) inventory with backorders, Two-echelon supply chain (library assets) |
| System dynamics | Bass diffusion, Inventory with lead time, Population (logistic), SIR epidemic, Training pipeline with attrition, Workforce (goal-seeking) |
| Teaching | Chance-based branching (DECIDE), HOLD on a store's contents, Delay, seize/release and signal HOLD, Policy-routed parallel servers, Single server (M/M/1), Single server, general service times (M/G/1), Process time lookup table, Tank: fill, overflow and run dry, Two tellers (resource set) |
Run one, read one¶
A command that takes a model file also takes the name of a bundled model, when no file of that name is there. naga examples lists the names; --path prints the folder the files are in, to read or copy one:
naga examples
naga examples --path
Some models use submodels that came from the asset libraries of a separate product; the engine runs the submodels, and that product's artwork is not in the files.
How the numbers are made¶
tools/gen_engine_docs.py runs every model and writes these pages: seed 0, the model's own run length and warm-up, and as many replications as the model itself asks for, at most 3. Each number is the mean over those replications, at three significant digits, with the half-width of its 95% Student-t interval when there is more than one replication. A test regenerates every page and compares, so a number here is what the engine gives, on the version these pages were built from. Few replications make wide intervals: these are illustrations, not results to cite. The models whose answer is known exactly are compared with it on Reference models.
The diagrams are the model's own blocks and links, written as Mermaid text. They are drawn by a script your browser loads from unpkg.com, the one request these pages make to another site; without it a diagram shows as its text. A model of stocks and flows or of agents alone has no blocks to draw.