def __init__(self, f, u, eps, upwind_type='classical'):
"""
Constructor
Inputs:
f: Map, explicit kernel function
u: Map, velocity function
eps: double >0, diffusivity
upwind_scheme: str, type of upwind scheme used
"""
Kernel.__init__(self, f)
self.__upwind_type = upwind_type
self.__vel = u
self.__eps = eps
def __init__(self, u, dfdx=None, samples='all'):
"""
Constructor
"""
Kernel.__init__(self, u, dfdx=dfdx, F=None, samples=samples)
