diff --git a/script/local.py b/script/local.py
index d096525..8dfbe40 100644
--- a/script/local.py
+++ b/script/local.py
@@ -290,11 +290,11 @@ def set_file(file_name):
 
 class pol_mode_index(Readable):
     def read(self):  
-        mode = pol_mode.read
-        if mode = "LINEAR": return 0
-        if mode = "CIRC +": return 1
-        if mode = "CIRC -": return 2
-        return -1;
+        mode = pol_mode.read()
+        if mode == "LINEAR": return 0.0
+        if mode == "CIRC +": return 1.0
+        if mode == "CIRC -": return 2.0
+        return -1.0;
 pmi = pol_mode_index()