[Positioning] "Null" is a false friend

owlps-positioning/src/accesspoint.hh

@@ -127,7 +127,7 @@ inline void AccessPoint::set_channel(const unsigned int channel)
  * control is done, so you should pass a correct value.
  *
  * Note that set_channel() is more secure because a wrong channel
- * number will cause #frequency to be nullified.
+ * number will cause #frequency to be set to zero.
  */
 inline void AccessPoint::set_frequency(const unsigned long _frequency)
 {

owlps-positioning/src/area.cc

@@ -83,7 +83,7 @@ void Area::reorder_coordinates()
     }
 
   // First point is South-West
-  // (or other cases such as null coordinates)
+  // (or other cases such as coordinates equal to zero)
   else
     {
       // We swap nothing