I am using a C band radar with radar fields [‘DBZ’, ‘PHIDP’, ‘RHOHV’, ‘VEL’, ‘WIDTH’, ‘ZDR’]

for phase processing i was using this code

phidp, kdp = pyart.correct.phase_proc_lp(radar, 0.0,refl_field=‘DBZ’,phidp_field=‘PHIDP’,rhv_field=‘RHOHV’,ncp_field=‘RHOHV’ ,LP_solver = “cvxopt”,debug=True)

error :

Cell In[4], line 6

1 # the next line force only the first sweep to be processed, this

2 # significantly speeds up the calculation but should be commented out

3 # in production so that the entire volume is processed

4 radar.sweep_start_ray_index[‘data’] = np.array([0])

----> 6 phidp, kdp = pyart.correct.phase_proc_lp(radar, 0.0,refl_field=‘DBZ’,phidp_field=‘PHIDP’,rhv_field=‘RHOHV’,ncp_field=‘RHOHV’ ,LP_solver = “cvxopt”,debug=True)

8 radar.add_field(‘proc_dp_phase_shift’, phidp)

9 radar.add_field(‘recalculated_diff_phase’, kdp)

File ~\anaconda3\Lib\site-packages\pyart\correct\phase_proc.py:1196, in phase_proc_lp(radar, offset, debug, self_const, low_z, high_z, min_phidp, min_ncp, min_rhv, fzl, sys_phase, overide_sys_phase, nowrap, really_verbose, LP_solver, refl_field, ncp_field, rhv_field, phidp_field, kdp_field, unf_field, window_len, proc, coef)

1192 mysoln = LP_solver_pyglpk(

1193 A_Matrix, B_vectors, nw, really_verbose=really_verbose

1194 )

1195 elif LP_solver == “cvxopt”:

→ 1196 mysoln = LP_solver_cvxopt(A_Matrix, B_vectors, nw)

1197 elif LP_solver == “cylp”:

1198 mysoln = LP_solver_cylp(

1199 A_Matrix, B_vectors, nw, really_verbose=really_verbose

1200 )

File ~\anaconda3\Lib\site-packages\pyart\correct\phase_proc.py:720, in LP_solver_cvxopt(A_Matrix, B_vectors, weights, solver)

718 this_soln = np.zeros(n_gates)

719 for i in range(n_gates):

→ 720 this_soln[i] = sol[“x”][i + n_gates]

722 # apply smoothing filter and record in output array

723 mysoln[raynum, :] = smooth_and_trim(this_soln, window_len=5, window=“sg_smooth”)

TypeError: ‘NoneType’ object is not subscriptable

if anyone has insights on how to solve this I would greatly appreciate your guidance