further improvements

src/raster/r.vif/r.vif.py

@@ -205,7 +205,7 @@ def read_data(raster, n, flag_s, seed):
 def compute_vif(mapx, mapy):
     """Compute rsqr of linear regression between layers mapx and mapy."""
     x_i = np.hstack((mapx, np.ones((mapx.shape[0], 1))))
-    _, resid = np.linalg.lstsq(x_i, mapy, rcond=None)[:2]
+    unused, resid = np.linalg.lstsq(x_i, mapy, rcond=None)[:2]
     if resid.size == 0:
         resid = 0
     r2 = float(1 - resid / (mapy.size * mapy.var()))
@@ -240,16 +240,16 @@ def main(options, flags):
 
     # Variables
     input_maps = options["maps"].split(",")
-    retain_map = options["retain"].split(",")
-    if retain_map != [""]:
-        check_layer(retain_map)
-        for k, _ in enumerate(retain_map):
-            if retain_map[k] not in input_maps:
-                input_maps.extend([retain_map[k]])
+    retain_maps = options["retain"].split(",")
+    if retain_maps != [""]:
+        check_layer(retain_maps)
+        for retain_map in retain_maps:
+            if retain_map not in input_maps:
+                input_maps.extend([retain_map])
     input_map_names = [i.split("@")[0] for i in input_maps]
-    retain_map_names = [i.split("@")[0] for i in retain_map]
+    retain_map_names = [i.split("@")[0] for i in retain_maps]
     max_vif = options["maxvif"]
-    if max_vif != "":
+    if max_vif:
         max_vif = float(max_vif)
     output_file = options["file"]
     number_points = options["n"]
@@ -330,8 +330,7 @@ def main(options, flags):
 
             # print the header of the output table to the console
             if not flag_v:
-                print("\n")
-                print("VIF round " + str(m))
+                print("\nVIF round " + str(m))
                 print("--------------------------------------")
                 print(
                     "{0[0]:{1}s} {0[1]:>8s} {0[2]:>8s}".format(
@@ -388,8 +387,7 @@ def main(options, flags):
 
         # Write final selected variables to std output
         if not flag_v:
-            print("/n")
-            print("selected variables are: ")
+            print("\nselected variables are: ")
             print("--------------------------------------")
             print(", ".join(input_map_names))
         else:
@@ -400,15 +398,15 @@ def main(options, flags):
             text_file = open(output_file, "w")
             if max_vif == "":
                 text_file.write("variable,vif,sqrtvif\n")
-                for i, _ in enumerate(out_vif):
+                for i in range(len(out_vif)):
                     text_file.write(
                         "{0:s},{1:.6f},{2:.6f}\n".format(
                             out_variable[i], out_vif[i], out_sqrt[i]
                         )
                     )
             else:
                 text_file.write("round,removed,variable,vif,sqrtvif\n")
-                for i, _ in enumerate(out_vif):
+                for i in range(len(out_vif)):
                     text_file.write(
                         "{0:d},{1:s},{2:s},{3:.6f},{4:.6f}\n".format(
                             out_round[i],
@@ -420,8 +418,7 @@ def main(options, flags):
                     )
         finally:
             text_file.close()
-            gs.message("\n")
-            gs.message("Statistics are written to " + output_file + "\n")
+            gs.message("\nStatistics are written to {}\n".format(output_file))
 
 
 if __name__ == "__main__":