:py:mod:`gnome.movers.py_current_movers`
========================================

.. py:module:: gnome.movers.py_current_movers


Module Contents
---------------

Classes
~~~~~~~

.. autoapisummary::

   gnome.movers.py_current_movers.CurrentMover



Functions
~~~~~~~~~

.. autoapisummary::

   gnome.movers.py_current_movers.grid_current_mover



Attributes
~~~~~~~~~~

.. autoapisummary::

   gnome.movers.py_current_movers.PyCurrentMoverSchema
   gnome.movers.py_current_movers.PyCurrentMover


.. py:data:: PyCurrentMoverSchema

   

.. py:class:: CurrentMover(current=None, time_offset=0, scale_value=1, uncertain_duration=24 * 3600, uncertain_time_delay=0, uncertain_along=0.5, uncertain_cross=0.25, default_num_method='RK2', filename=None, **kwargs)


   Bases: :py:obj:`gnome.movers.movers.PyMover`

   CurrentMover implemented in Python. Uses the .current attribute to move particles.
   The .at() interface is expected on the .current attribute

   Initialize a CurrentMover

   :param current: Environment object representing ocean currents to be
                   used.
   :type current: Any Current or Current-like that implements the .at() function

   :param active_range: Range of datetimes for when the mover should be
                        active
   :type active_range: 2-tuple of datetimes

   :param scale_value: Value to scale current data
   :param uncertain_duration: how often does a given uncertain element
                              get reset in seconds
   :param uncertain_time_delay: when does the uncertainly kick in in seconds
   :param uncertain_cross: Scale for uncertainty perpendicular to the flow
   :param uncertain_along: Scale for uncertainty parallel to the flow
   :param time_offset: Time zone shift: not functional
   :param default_num_method: Numerical method for calculating movement delta.
                              Choices:('Euler', 'RK2', 'RK4')
                              Default: RK2

   .. py:property:: filename


   .. py:property:: data_start


   .. py:property:: data_stop


   .. py:attribute:: _schema

      

   .. py:attribute:: _ref_as
      :value: 'py_current_movers'

      

   .. py:attribute:: _req_refs

      

   .. py:method:: from_netCDF(filename=None, name=None, time_offset=0, scale_value=1, uncertain_duration=24 * 3600, uncertain_time_delay=0, uncertain_along=0.5, uncertain_cross=0.25, **kwargs)
      :classmethod:

      Function for specifically creating a CurrentMover from a file


   .. py:method:: get_bounds()

      Return a bounding box surrounding the grid data.
      This function exists because it is part of the top level Mover API


   .. py:method:: get_move(sc, time_step, model_time_datetime, num_method=None)

      Compute the move in (long,lat,z) space. It returns the delta move
      for each element of the spill as a numpy array of size
      (number_elements X 3) and dtype = gnome.basic_types.world_point_type

      Base class returns an array of numpy.nan for delta to indicate the
      get_move is not implemented yet.

      Each class derived from Mover object must implement it's own get_move

      :param sc: an instance of gnome.spill_container.SpillContainer class
      :param time_step: time step in seconds
      :param model_time_datetime: current model time as datetime object

      All movers must implement get_move() since that's what the model calls


   .. py:method:: _update_uncertainty(num_les, elapsed_time)

      update uncertainty

      :param num_les: the number released so far
      :param elapsed_time: time in seconds since model run started


   .. py:method:: _update_uncertainty_values(elapsed_time)

      update uncertainty values

      :param elapsed_time: time in seconds since model run started


   .. py:method:: _allocate_uncertainty(num_les)

      add uncertainty

      :param num_les: the number of les released so far


   .. py:method:: _add_uncertainty(deltas)

      add uncertainty

      :param deltas: the movement for the current time step


   .. py:method:: prepare_for_model_run()

      reset uncertainty


   .. py:method:: prepare_for_model_step(sc, time_step, model_time_datetime)

      add uncertainty


   .. py:method:: model_step_is_done(sc)

      remove any off map les



.. py:data:: PyCurrentMover

   

.. py:function:: grid_current_mover(filename, current_kwargs=None, *args, **kwargs)

   Helper function to load a gridded current from a file and create a CurrentMover

   :param filename: File to create the GridCurrent object from
   :type filename: string or Path-like'

   :param current_kwargs: keyword arguments for the GridCurrent object. OPTIONAL
   :type current_kwargs: dict