Index: trunk/Ohana/src/opihi/cmd.astro/fitplx.c
===================================================================
--- trunk/Ohana/src/opihi/cmd.astro/fitplx.c	(revision 39234)
+++ trunk/Ohana/src/opihi/cmd.astro/fitplx.c	(revision 39610)
@@ -597,17 +597,20 @@
   dsort (values, Npts);
 
-  if (Npts % 2) {
-    int Ncenter = Npts / 2;
-    *median = values[Ncenter];
-  } else {
-    int Ncenter = Npts / 2 - 1;
-    *median = 0.5*(values[Ncenter] + values[Ncenter + 1]);
-  }
-
-  double Slo = VectorFractionInterpolate (values, 0.158655, Npts);
-  double Shi = VectorFractionInterpolate (values, 0.841345, Npts);
-
-  *sigma = (Shi - Slo) / 2.0;
-
+  if (median) {
+    if (Npts % 2) {
+      int Ncenter = Npts / 2;
+      *median = values[Ncenter];
+    } else {
+      int Ncenter = Npts / 2 - 1;
+      *median = 0.5*(values[Ncenter] + values[Ncenter + 1]);
+    }
+  }
+    
+  if (sigma) {
+    double Slo = VectorFractionInterpolate (values, 0.158655, Npts);
+    double Shi = VectorFractionInterpolate (values, 0.841345, Npts);
+    *sigma = (Shi - Slo) / 2.0;
+  }
+  
   return TRUE;
 }