updates warning messages

TurTLE/PP.py

@@ -802,7 +802,7 @@ class PP(_code):
                 if os.path.exists(cpf_name):
                     cpf = h5py.File(cpf_name, 'r')
                     if 'vorticity' not in cpf.keys():
-                        print('file ', cpf_name, ' does not have vorticity group')
+                        print('TurTLE warning: file ', cpf_name, ' does not have vorticity group')
                     else:
                         for iter_name in cpf['vorticity/complex'].keys():
                             if iter_name not in ff['vorticity/complex'].keys():
@@ -810,7 +810,7 @@ class PP(_code):
                                         cpf_name,
                                         'vorticity/complex/' + iter_name)
                     if 'velocity' not in cpf.keys():
-                        print('file ', cpf_name, ' does not have velocity group')
+                        print('TurTLE warning: file ', cpf_name, ' does not have velocity group')
                     else:
                         if 'complex' in cpf['velocity'].keys():
                             for iter_name in cpf['velocity/complex'].keys():