pydda.cost_functions.calculate_model_gradient¶
-
pydda.cost_functions.
calculate_model_gradient
(u, v, w, weights, u_model, v_model, w_model, coeff=1.0)[source]¶ Calculates the cost function for the model constraint. This is calculated simply as twice the differences between the model wind field and the analysis wind field for each u, v. Vertical velocities are not factored into this cost function as there is typically a high amount of uncertainty in model derived vertical velocities. Therefore, the gradient for all of the w’s will be 0.
Parameters: u: Float array
Float array with u component of wind field
v: Float array
Float array with v component of wind field
w: Float array
Float array with w component of wind field
weights: list of 3D float arrays
Weights for each point to consider into cost function
u_model: list of 3D float arrays
Zonal wind field from model
v_model: list of 3D float arrays
Meridional wind field from model
w_model: list of 3D float arrays
Vetical wind field from model
coeff: float
Weight of background constraint to total cost function
Returns: y: float array
value of gradient of background cost function