gnome.movers.c_wind_movers¶

Movers using wind as the forcing function

Attributes¶

`WindMoverSchema`
`WindMover`

Classes¶

`WindMoversBase`	Base class from which all Python movers/weatherers can inherit
`PointWindMover`	Python wrapper around the Cython wind_mover module.
`c_GridWindMover`	Base class from which all Python movers/weatherers can inherit
`IceWindMover`	Base class from which all Python movers/weatherers can inherit

Functions¶

`point_wind_mover_from_file`(filename, **kwargs)	Creates a wind mover from a wind time-series file (OSM long wind format)
`constant_point_wind_mover`(speed, direction[, units])	utility function to create a point wind mover with a constant wind

Module Contents¶

class gnome.movers.c_wind_movers.WindMoversBase(uncertain_duration=3, uncertain_time_delay=0, uncertain_speed_scale=2.0, uncertain_angle_scale=0.4, **kwargs)¶

Bases: gnome.movers.CyMover

Base class from which all Python movers/weatherers can inherit

It defines the base functionality for mover/weatherer.

NOTE: Since base class is not Serializable, it does not need: a class level _schema attribute.

This is simply a base class for WindMover and c_GridWindMover for the common properties.

The classes that inherit from this should define the self.mover object correctly so it has the required attributes.

Input args with defaults:

Parameters:

uncertain_duration – (seconds) the randomly generated uncertainty array gets recomputed based on ‘uncertain_duration’
uncertain_time_delay – when does the uncertainly kick in.
uncertain_speed_scale – Scale for uncertainty in wind speed non-dimensional number
uncertain_angle_scale – Scale for uncertainty in wind direction. Assumes this is in radians

It calls super in the __init__ method and passes in the optional parameters (kwargs)

property uncertain_duration¶

property uncertain_time_delay¶

uncertain_speed_scale = 2.0¶

uncertain_angle_scale = 0.4¶

prepare_for_model_step(sc, time_step, model_time_datetime)¶

Call base class method using super Also updates windage for this timestep

Parameters:

sc – an instance of gnome.spill_container.SpillContainer class
time_step – time step in seconds
model_time_datetime – current time of model as a date time object

get_move(sc, time_step, model_time_datetime)¶

Override base class functionality because mover has a different get_move signature

Parameters:

sc – an instance of the gnome.SpillContainer class
time_step – time step in seconds
model_time_datetime – current time of the model as a date time object

gnome.movers.c_wind_movers.WindMoverSchema¶

class gnome.movers.c_wind_movers.PointWindMover(wind=None, **kwargs)¶

Bases: WindMoversBase

Python wrapper around the Cython wind_mover module. This class inherits from CyMover and contains CyWindMover

The real work is done by the CyWindMover object. CyMover sets everything up that is common to all movers.

Uses super to call CyMover base class __init__

Parameters:: wind – wind object – provides the wind time series for the mover

Remaining kwargs are passed onto WindMoversBase __init__ using super. See Mover documentation for remaining valid kwargs.

Note

Can be initialized with wind=None; however, wind must be set before running. If wind is not None, toggle make_default_refs to False since user provided a valid Wind and does not wish to use the default from the Model.

mover¶

property wind¶

property data_start¶

property data_stop¶

prepare_for_model_run()¶: if wind attribute is not set, raise ReferencedObjectNotSet excpetion

gnome.movers.c_wind_movers.WindMover¶

gnome.movers.c_wind_movers.point_wind_mover_from_file(filename, **kwargs)¶

Creates a wind mover from a wind time-series file (OSM long wind format)

Parameters:

filename – The full path to the data file
kwargs – All keyword arguments are passed on to the WindMover constructor

Returns mover:

returns a wind mover, built from the file

gnome.movers.c_wind_movers.constant_point_wind_mover(speed, direction, units='m/s')¶

utility function to create a point wind mover with a constant wind

Parameters:

speed – wind speed
direction – wind direction in degrees true (direction from, following the meteorological convention)
units='m/s' – the units that the input wind speed is in. options: ‘m/s’, ‘knot’, ‘mph’, others…

Returns:

returns a gnome.movers.WindMover object all set up.

Note

The time for a constant wind timeseries is irrelevant. This function simply sets it to datetime.now() accurate to hours.

class gnome.movers.c_wind_movers.c_GridWindMover(filename=None, topology_file=None, extrapolate=False, time_offset=0, **kwargs)¶

Bases: WindMoversBase

Base class from which all Python movers/weatherers can inherit

It defines the base functionality for mover/weatherer.

NOTE: Since base class is not Serializable, it does not need: a class level _schema attribute.

Parameters:

wind_file – file containing wind data on a grid
filename – file containing wind data on a grid
topology_file – Default is None. When exporting topology, it is stored in this file
wind_scale – Value to scale wind data
extrapolate – Allow current data to be extrapolated before and after file data
time_offset – Time zone shift if data is in GMT

Pass optional arguments to base class uses super: super(c_GridWindMover,self).__init__(**kwargs)

mover¶

name¶: define as property in base class so all objects will have a name by default

filename = None¶

topology_file = None¶

property data_start¶

property data_stop¶

wind_scale¶

extrapolate¶

time_offset¶

get_grid_data()¶

get_cells()¶: Invokes the GetCellDataHdl method of TimeGridWind_c object. Cross-references point data to get cell coordinates.

get_points()¶

get_cell_center_points()¶

Right now the cython mover only gets the triangular center points, so we need to calculate centers based on the cells themselves.

Cells will have the format (tl, tr, bl, br) We need to get the rectangular centers Center will be: (tl + ((br - tl) / 2.))

get_center_points()¶

get_scaled_velocities(time)¶

Parameters:: model_time=0

export_topology(topology_file)¶

Parameters:: topology_file=None – absolute or relative path where topology file will be written.

extrapolate_in_time(extrapolate)¶

Parameters:: extrapolate=false – Allow current data to be extrapolated before and after file data.

offset_time(time_offset)¶

Parameters:: offset_time=0 – Allow data to be in GMT with a time zone offset (hours).

class gnome.movers.c_wind_movers.IceWindMover(filename=None, topology_file=None, extrapolate=False, time_offset=0, **kwargs)¶

Bases: WindMoversBase

Base class from which all Python movers/weatherers can inherit

It defines the base functionality for mover/weatherer.

NOTE: Since base class is not Serializable, it does not need: a class level _schema attribute.

Initialize an IceWindMover

Parameters:

filename – absolute or relative path to the data file: could be netcdf or filelist
topology_file=None – absolute or relative path to topology file. If not given, the IceMover will compute the topology from the data file.
active_range (2-tuple of datetimes) – Range of datetimes for when the mover should be active
wind_scale – Value to scale wind data
extrapolate – Allow current data to be extrapolated before and after file data
time_offset – Time zone shift if data is in GMT

uses super, super(IceWindMover,self).__init__(**kwargs)

name¶: define as property in base class so all objects will have a name by default

filename = None¶

topology_file = None¶

extrapolate = False¶

get_grid_data()¶

get_center_points()¶

get_scaled_velocities(model_time)¶

Parameters:: model_time=0

get_ice_velocities(model_time)¶

Parameters:: model_time=0

get_movement_velocities(model_time)¶

Parameters:: model_time=0

get_ice_fields(model_time)¶

Parameters:: model_time=0

export_topology(topology_file)¶

Parameters:: topology_file=None – absolute or relative path where topology file will be written.

extrapolate_in_time(extrapolate)¶

Parameters:: extrapolate=false – allow current data to be extrapolated before and after file data.

offset_time(time_offset)¶

Parameters:: offset_time=0 – allow data to be in GMT with a time zone offset (hours).

get_offset_time()¶

Parameters:: offset_time=0 – allow data to be in GMT with a time zone offset (hours).