Index: trunk/FACT++/src/smartfact.cc
===================================================================
--- trunk/FACT++/src/smartfact.cc	(revision 17168)
+++ trunk/FACT++/src/smartfact.cc	(revision 17169)
@@ -685,6 +685,5 @@
 
             const size_t p = t.size()/2;
-
-            med = copy[p];
+            med = p%2 ? copy[p] : (copy[p-1]+copy[p])/2.;
         }
     };
@@ -1697,5 +1696,7 @@
 
         avg /= num;
-        rms = sqrt(rms/num-avg*avg);
+        rms /= num;
+        rms += avg*avg;
+        rms = rms<0 ? 0 : sqrt(rms);
 
         if (!fMagicWeatherHist[kTemp].empty())