add method to subset by time from product file

modules/aeolus/aeolus_amv.py

@@ -437,3 +437,68 @@ def create_amv_to_aeolus_match_file(aeolus_files_dir, amv_files_dir, outfile=Non
     if outfile is not None:
         create_file(outfile, m_d, a_d)
 
+
+def get_subset(pathname, t_0, t_1):
+    rootgrp = Dataset(pathname, 'r', format='NETCDF4')
+    all_dims = rootgrp.dimensions
+    t_var = rootgrp['time']
+
+    n_profs = len(all_dims['num_aeolus_profs'])
+    n_amvs_per_prof = rootgrp['num_amvs_per_prof'][:]
+    n_levs_per_prof = rootgrp['num_levs_per_prof'][:]
+
+    a_dir_v = rootgrp['amv_dir']
+    a_spd_v = rootgrp['amv_spd']
+    a_dst_v = rootgrp['amv_dist']
+    a_prs_v = rootgrp['amv_pres']
+
+    p_azm_v = rootgrp['prof_azm']
+    p_spd_v = rootgrp['prof_spd']
+    p_hhb_v = rootgrp['prof_hhb']
+    p_hht_v = rootgrp['prof_hht']
+
+    times = t_var[:]
+    time_idxs = np.arange(n_profs)
+    valid = np.logical_and(times >= t_0, times < t_1)
+    time_idxs = time_idxs[valid]
+    n_times = time_idxs.shape[0]
+
+    prf_idx_start = np.sum(n_levs_per_prof[0:time_idxs[0]])
+    amv_idx_start = np.sum(n_amvs_per_prof[0:time_idxs[0]])
+
+    mx_namvs = np.max(n_amvs_per_prof[amv_idx_start:amv_idx_start+n_times])
+    mx_nlevs = np.max(n_levs_per_prof[prf_idx_start:prf_idx_start+n_times])
+
+    amvs = np.zeros((n_times, mx_namvs, 4))
+    profs = np.zeros((n_times, mx_nlevs, 4))
+    amvs.fill(np.nan)
+    profs.fill(np.nan)
+
+    accum_prf = 0
+    accum_amv = 0
+    for idx, t_i in enumerate(time_idxs):
+        n_amvs = n_amvs_per_prof[t_i]
+        n_levs = n_levs_per_prof[t_i]
+
+        a = accum_amv
+        b = accum_amv + n_amvs
+
+        c = accum_prf
+        d = accum_prf + n_levs
+
+        amvs[idx:, 0:n_amvs, 0] = a_spd_v[a:b]
+        amvs[idx, 0:n_amvs, 1] = a_dir_v[a:b]
+        amvs[idx, 0:n_amvs, 2] = a_prs_v[a:b]
+        amvs[idx, 0:n_amvs, 3] = a_dst_v[a:b]
+
+        profs[idx, 0:n_levs, 0] = p_spd_v[c:d]
+        profs[idx, 0:n_levs, 1] = p_azm_v[c:d]
+        profs[idx, 0:n_levs, 2] = p_hhb_v[c:d]
+        profs[idx, 0:n_levs, 3] = p_hht_v[c:d]
+
+        accum_amv += n_amvs
+        accum_prf += n_levs
+
+    return amvs, profs, times[time_idxs]
+
+