diff --git a/src/io.f90 b/src/io.f90
index 29ac73e..f168a4f 100644
--- a/src/io.f90
+++ b/src/io.f90
@@ -150,7 +150,7 @@ module io
             outn = outn + 1
         end do
 
-        if((outn-atom_num) /= atom_num) then 
+        if((outn-node_num) /= atom_num) then 
             print *, "outn", (outn-node_num), " doesn't equal atom_num ", atom_num
         end if