diff --git a/colib/narray-util.h b/colib/narray-util.h
index 5bfd13f..56ff40f 100644
--- a/colib/narray-util.h
+++ b/colib/narray-util.h
@@ -31,7 +31,7 @@
 #ifndef h_narray_util__
 #define h_narray_util__
 
-#include <math.h>
+#include <cmath>
 #include <stdlib.h>
 #include "colib/checks.h"
 #include "misc.h"
@@ -176,7 +176,7 @@ namespace colib {
         double total = 0.0;
         for(int i=0;i<a.length1d();i++)
             total += sqr(a.at1d(i)-b.at1d(i));
-        CHECK_ARG(!isnan(total));
+        CHECK_ARG(!std::isnan(total));
         return total;
     }
 
diff --git a/commands/iuedges b/commands/iuedges
new file mode 100755
index 0000000..32a2c0f
Binary files /dev/null and b/commands/iuedges differ
diff --git a/imglib/imgops.cc b/imglib/imgops.cc
index 50bb96c..e35b8f2 100644
--- a/imglib/imgops.cc
+++ b/imglib/imgops.cc
@@ -133,7 +133,7 @@ namespace iulib {
 
     template<class T,class V>
     void addscaled(narray<T> &dest,narray<T> &src,
-            V scale=1,int dx=0,int dy=0) {
+            V scale,int dx,int dy) {
         for (int i=0; i<dest.dim(0); i++)
             for (int j=0; j<dest.dim(1); j++)
                 dest.unsafe_at(i,j) += (T)(scale*xref(src,i+dx,j+dy));
diff --git a/imglib/imgops.h b/imglib/imgops.h
index 2fdb156..ef3b818 100644
--- a/imglib/imgops.h
+++ b/imglib/imgops.h
@@ -67,7 +67,7 @@ namespace iulib {
     }
 
     template<class T, class V>
-    void addscaled(colib::narray<T> &, colib::narray<T> &, V, int, int);
+    void addscaled(colib::narray<T> &, colib::narray<T> &, V scale=1,int dx=0,int dy=0);
     template<class T>
     void tighten(colib::narray<T> &image);
     template<class T>