API Reference

This section documents the main classes in the ANUGA public API. For a complete alphabetical index of all names exported by the anuga package see the Index.

The three classes below form the foundation of every ANUGA simulation:

Class	Role
`Domain`	The simulation domain — owns the mesh, quantities, operators, boundary conditions, and the evolve loop. This is the central object in any ANUGA script.
`Quantity`	Represents a single physical field (elevation, stage, friction, xmomentum, ymomentum) on the mesh. Accessed via `domain.quantities['stage']` etc. Provides methods for setting values, computing integrals, interpolation, and extrapolation.
`Region`	A spatial subset of the mesh defined by a polygon or list of triangle indices. Used to apply operators or set quantities over a specific area of the domain.

Domain

The Domain class is the top-level simulation object. A typical script:

Creates a Domain from a mesh (rectangular grid or unstructured mesh from create_domain_from_regions).
Sets initial conditions on its Quantity objects via domain.set_quantity().
Assigns boundary conditions to named boundary tags via domain.set_boundary().
Optionally attaches operators (rainfall, culverts, inlets).
Calls domain.evolve() to advance the simulation in time.

Domain

Object which encapulates the shallow water model

Full Domain API

Quantity

Quantity objects are created automatically by the Domain and are not usually instantiated directly. They are accessed via domain.quantities:

elev = domain.quantities['elevation']
print(elev.centroid_values)     # values at triangle centroids
print(elev.vertex_values)       # values at triangle vertices
print(elev.get_integral())      # integral over the domain

Each quantity allocates only the arrays it needs via the qty_type parameter ('evolved', 'centroid_only', 'edge_diagnostic', or 'coordinate'). Gradient and phi arrays are lazy for all types. See Memory layout (qty_type) for details.

Quantity

Class Quantity - Implements values at each triangular element

Full Quantity API

Region

A Region identifies a spatial subset of the mesh. It is typically created by passing a polygon to an operator or by calling domain.get_region(), and it provides the list of triangle indices that fall inside the polygon. Operators use regions to apply forcing (rainfall, extraction) only over a defined area.

import anuga

polygon = [[0, 0], [5, 0], [5, 5], [0, 5]]
region = anuga.Region(domain, polygon=polygon)
print(region.get_indices())    # triangle IDs inside the polygon

Region

Object which defines a region within the domain

Full Region API

Geo_reference

Geo_reference records the coordinate reference system (CRS) and local origin of an ANUGA domain. It supports WGS84 UTM zones (auto-computed EPSG), national grids such as RD New (EPSG:28992) or British National Grid (EPSG:27700), and arbitrary local systems for wavetank simulations.

geo_ref = anuga.Geo_reference(zone=55, hemisphere='southern',
                              xllcorner=363000.0, yllcorner=8132000.0)
geo_ref.epsg          # 32755  (auto-computed)
geo_ref.is_located()  # True

# Or supply EPSG directly (zone and hemisphere inferred for UTM codes):
geo_ref = anuga.Geo_reference(epsg=32755, xllcorner=363000.0, yllcorner=8132000.0)

# National grids work too:
geo_ref = anuga.Geo_reference(epsg=28992)   # Netherlands RD New

See Coordinate Reference Systems for full usage guidance.

Full Geo_reference API

File format reference

Reference documentation for all file formats read and written by ANUGA — SWW, STS, TMS, mesh files (TSH/MSH), DEM formats, and point data.

File format reference

Validation test suite

Description of the validation tests in validation_tests/, how to run them, and what physical benchmarks they cover.

Validation test suite