Fixed the reading order of errors for GOVO

pygeodyn/inout/observations.py

@@ -79,7 +79,10 @@ def build_go_vo_observations(cfg, nb_realisations, measure_type):
             raise IOError(
                 "Variance {} file for observations was not found ! Check that {} is a valid file path.".format(
                     measure_type, var_path))
-        var_data = np.loadtxt(var_path)
+        # Take only the diagonal of the variance
+        var_data = np.diag(np.loadtxt(var_path))
+        assert len(var_data) % 3 == 0
+        numberofVOs = len(var_data)//3
 
         # Draw a seed for normal draw
         seed = np.random.randint(0, 50000)
@@ -101,8 +104,9 @@ def build_go_vo_observations(cfg, nb_realisations, measure_type):
                 for j in range(0, 3):
                     n = 3 * i_obs + j
                     # Extract the var_data of the current observation thanks to the obs_id
+                    # Format: [Br1, Br2, ..., BrN, Bth1, ..., BthN, Bph1, ..., BphN]
                     # The value stored is assumed to be sigma**2
-                    sigma2 = var_data[3 * obs_id + j, 3 * obs_id + j]
+                    sigma2 = var_data[j*numberofVOs + obs_id]
                     var_at_date.append(sigma2)
                     # Noise data with normal noise N(data, sigma)
                     noised_data_at_date[:, n] = random_draw(obs_data[date][n], math.sqrt(sigma2), size=nb_realisations)