class Lagrangian:
"""
This class provides pure Lagrangian kernels.
The particle just follows the local velocity flow field.
Attributes:
-Vi (function): The interpolant function, to evaluate the
local flow velocity field V(r(t),t).
"""
def __init__(self,json_dict):
"""
Lagrangian kernel constructor.
Args:
Vi (function): Interpolant function.
"""
self.Vi = InputFields()
self.Vi.get_info(json_dict['velocity'])
self.Vi.get_mfds()
self.Vi.get_grid()
self.Vi.get_interpolants()
self.boundaries = []
def F(self, r, t):
"""
Model Kernel function to send to the solver module.
Args:
r (array): Array containing the position of the particles [space_units].
t (float): Time instant [time_units]
Returns:
array: Array containing the velocity componentes evaluted. [space_units/time_units]
"""
if self.boundaries:
r = self.boundaries.F(r)
return self.Vi.F(r, t)
class LagrangianSpherical2D:
"""
This class provides Lagrangian Kernels, for spherical (lat,lon) integrations,
considering a perfectly spherical earth with a 6370Km radius.
The particle just follows the local flow velocity field.
Attributes:
- m_to_deg (float): Conversion from [m/s] to [degrees/s].
- Vi (function): The interpolant function, to evaluate the local flow velocity field V(r(t),t).
"""
def __init__(self, json_dict):
"""
Lagrangian kernel constructor.
Args:
Vi (function): Interpolant function.
"""
self.m_to_deg = (np.pi/180.)*6370000.
self.Vi = InputFields()
self.Vi.get_info(json_dict['velocity'])
self.Vi.get_mfds()
self.Vi.get_grid()
self.Vi.get_interpolants()
def F(self, r, t):
"""
Model Kernel function to send to the solver module.
Args:
- r (array): Array containing the position of the particles [space_units].
- t (float): Time instant [time_units].
Returns:
- array: Array containing the velocity componentes evaluted [space_units/time_units].
"""
drdt = self.Vi.F(r, t)
drdt[:,0] = drdt[:,0]/(self.m_to_deg*np.cos((np.pi/180.)*r[:,1]))
drdt[:,1] = drdt[:,1]/self.m_to_deg
return drdt