pydda.cost_functions.calculate_radial_vel_cost_function#

pydda.cost_functions.calculate_radial_vel_cost_function(vrs, azs, els, u, v, w, wts, rmsVr, weights, coeff=1.0)[source]#

Calculates the cost function due to difference of the wind field from radar radial velocities. For more information on this cost function, see Potvin et al. (2012) and Shapiro et al. (2009). All arrays in the given lists must have the same dimensions and represent the same spatial coordinates. :Parameters: * vrs (List of float arrays) – List of radial velocities from each radar

  • els (List of float arrays) – List of elevations from each radar

  • azs (List of float arrays) – List of azimuths from each radar

  • 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

  • wts (List of float arrays) – Float array containing fall speed from radar.

  • rmsVr (float) – The sum of squares of velocity/num_points. Use for normalization of data weighting coefficient

  • weights (n_radars x_bins x y_bins float array) – Data weights for each pair of radars

  • coeff (float) – Constant for cost function

Returns:

J_o (float) – Observational cost function

References

Potvin, C.K., A. Shapiro, and M. Xue, 2012: Impact of a Vertical Vorticity Constraint in Variational Dual-Doppler Wind Analysis: Tests with Real and Simulated Supercell Data. J. Atmos. Oceanic Technol., 29, 32–49, https://doi.org/10.1175/JTECH-D-11-00019.1 Shapiro, A., C.K. Potvin, and J. Gao, 2009: Use of a Vertical Vorticity Equation in Variational Dual-Doppler Wind Analysis. J. Atmos. Oceanic Technol., 26, 2089–2106, https://doi.org/10.1175/2009JTECHA1256.1