diff --git a/include/ceres/jet.h b/include/ceres/jet.h
index 552df65..e94df5d 100644
--- a/include/ceres/jet.h
+++ b/include/ceres/jet.h
@@ -650,6 +650,10 @@
   typedef ceres::Jet<T, N> NonInteger;
   typedef ceres::Jet<T, N> Nested;
 
+  static typename ceres::Jet<T, N> dummy_precision() {
+    return ceres::Jet<T, N>(1e-12);
+  }
+
   enum {
     IsComplex = 0,
     IsInteger = 0,