anuga.Field_boundary

class anuga.Field_boundary(filename, domain, mean_stage=0.0, time_thinning=1, time_limit=None, boundary_polygon=None, default_boundary=None, use_cache=False, verbose=False)[source]

Bases: Boundary

Boundary condition driven by an SWW field file with optional stage offset.

Reads stage, x-momentum and y-momentum time series from an SWW file and applies them as a boundary condition, linearly interpolating in time. An optional mean_stage offset can be added to the stage values, which avoids regenerating the SWW file when running at different tide levels.

This is a thin wrapper around File_boundary; the only difference is the mean_stage offset capability.

Parameters:

  • filename (str) – Path to the SWW file containing stage and momentum time series.

  • domain (anuga.Domain) – The domain to which this boundary is attached.

  • mean_stage (float, optional) – Constant offset added to the stage read from the file. Useful for running at different tidal datums without recreating the SWW file. Default 0.0.

  • time_thinning (int, optional) – Read every time_thinning-th time step from the file. Larger values speed up model setup at the cost of temporal resolution. Default 1 (all steps).

  • time_limit (float or None, optional) – Stop reading the file after this time (seconds). None means read to the end.

  • boundary_polygon (list or None, optional) – Clip the SWW points to this polygon. None means use all points.

  • default_boundary (float or None, optional) – Stage returned when model time exceeds the file’s time range. None raises an exception on out-of-range.

  • use_cache (bool, optional) – Cache the interpolated field function. Default False.

  • verbose (bool, optional) – Emit progress messages. Default False.

Examples

>>> import anuga
>>> domain = anuga.rectangular_cross_domain(10, 10)
>>> Bf = anuga.Field_boundary('boundary.sww', domain, mean_stage=0.5)
>>> domain.set_boundary({'left': Bf, 'right': Bf, 'top': Bf, 'bottom': Bf})
__init__(filename, domain, mean_stage=0.0, time_thinning=1, time_limit=None, boundary_polygon=None, default_boundary=None, use_cache=False, verbose=False)[source]

Initialise a field boundary.

Parameters:

  • filename (str) – Path to the SWW file.

  • domain (anuga.Domain) – The domain to which this boundary is attached.

  • mean_stage (float, optional) – Stage offset (m). Default 0.0.

  • time_thinning (int, optional) – Step stride when reading time steps. Default 1.

  • time_limit (float or None, optional) – Maximum time to read from file.

  • boundary_polygon (list or None, optional) – Polygon used to clip SWW points.

  • default_boundary (float or None, optional) – Fallback stage when model time is out of range.

  • use_cache (bool, optional) – Enable caching. Default False.

  • verbose (bool, optional) – Verbosity flag. Default False.

Methods

__init__(filename, domain[, mean_stage, ...])

Initialise a field boundary.

evaluate([vol_id, edge_id])

Calculate 'field' boundary results.

evaluate_segment([domain, segment_edges])

Evaluate boundary condition at edges of a domain in a list defined by segment_edges

get_boundary_values([t])

get_time()

evaluate(vol_id=None, edge_id=None)[source]

Calculate ‘field’ boundary results. vol_id and edge_id are ignored

Return linearly interpolated values based on domain.time