MNT: Convert some string concatenations to f-strings

src/metpy/interpolate/points.py

@@ -154,7 +154,7 @@ def natural_neighbor_point(xp, yp, variable, grid_loc, tri, neighbors, circumcen
         except (ZeroDivisionError, qhull.QhullError) as e:
             message = ('Error during processing of a grid. '
                        'Interpolation will continue but be mindful '
-                       'of errors in output. ') + str(e)
+                       f'of errors in output. {e}')
 
             log.warning(message)
             return np.nan
@@ -270,7 +270,7 @@ def inverse_distance_to_points(points, values, xi, r, gamma=None, kappa=None, mi
                 img[idx] = barnes_point(dists, values_subset, kappa, gamma)
 
             else:
-                raise ValueError(str(kind) + ' interpolation not supported.')
+                raise ValueError(f'{kind} interpolation not supported.')
 
     return img
 

src/metpy/io/nexrad.py

@@ -528,7 +528,7 @@ def _decode_msg18(self, msg_hdr):
             msg_fmt = DictStruct(fields, '>')
             self.rda = msg_fmt.unpack(data)
             for num in (11, 21, 31, 32, 300, 301):
-                attr = 'VCPAT' + str(num)
+                attr = f'VCPAT{num}'
                 dat = self.rda[attr]
                 vcp_hdr = self.vcp_fmt.unpack_from(dat, 0)
                 off = self.vcp_fmt.size
@@ -1703,8 +1703,8 @@ def __init__(self, filename):
         log.debug('Product description block: %s', self.prod_desc)
 
         # Convert thresholds and dependent values to lists of values
-        self.thresholds = [getattr(self.prod_desc, 'thr' + str(i)) for i in range(1, 17)]
-        self.depVals = [getattr(self.prod_desc, 'dep' + str(i)) for i in range(1, 11)]
+        self.thresholds = [getattr(self.prod_desc, f'thr{i}') for i in range(1, 17)]
+        self.depVals = [getattr(self.prod_desc, f'dep{i}') for i in range(1, 11)]
 
         # Set up some time/location metadata
         self.metadata['msg_time'] = nexrad_to_datetime(self.header.date,