import numpy as np

def Vorticity(u, v, dx, dy):

"""Calculates the Vorticity

Params:

-------

x, y 2D arrays of float, x and y direction points

u, v 2D arrays of float, u and v velocity vectors

Returns:

-------

Vorticity 2D array of float, curl of the velocity field

"""

dV = np.empty_like(v, dtype=float)

dU = np.empty_like(u, dtype=float)

dV = np.gradient(v)

dU = np.gradient(u)

V_gradient = dV[1]/dx

U_gradient = dU[0]/dy

Vorticity = V_gradient - U_gradient

Vorticity[-1,:] = Vorticity[0,:]

Vorticity[:,-1] = Vorticity[:,0]

Vorticity[-2,:] = Vorticity[-1,:]

Vorticity[:,-2] = Vorticity[:,-1]

return Vorticity