diff --git a/.ci/build_tarballs.jl b/.ci/build_tarballs.jl
index eb2d166..a45b342 100644
--- a/.ci/build_tarballs.jl
+++ b/.ci/build_tarballs.jl
@@ -13,7 +13,7 @@ julia_version = v"1.5.3"
 name = "LCIO_Julia_Wrapper"
 version = get(ENV, "TRAVIS_TAG", "")
 if version == ""
-	version = v"0.13.0-alpha4"
+	version = v"0.13.1-alpha1"
 else
 	version = VersionNumber(version)
 end
diff --git a/src/CalorimeterHitTypes.icc b/src/CalorimeterHitTypes.icc
index 86e0500..8ee5dd1 100644
--- a/src/CalorimeterHitTypes.icc
+++ b/src/CalorimeterHitTypes.icc
@@ -19,7 +19,12 @@ lciowrap.add_type<EVENT::SimCalorimeterHit>("SimCalorimeterHit")
 // returns a bool to indicate whether this was a nullptr
 lciowrap.method("getPosition3", [](const EVENT::SimCalorimeterHit* hit, ArrayRef<double> x)->bool {
     const float* p = hit->getPosition();
-    if (not p) return false;
+    if (not p) {
+        x[0] = nan("");
+        x[1] = nan("");
+        x[2] = nan("");
+        return false;
+    }
     x[0] = p[0];
     x[1] = p[1];
     x[2] = p[2];
@@ -42,7 +47,12 @@ lciowrap.add_type<EVENT::CalorimeterHit>("CalorimeterHit", jlcxx::julia_base_typ
     .method("getType", &EVENT::CalorimeterHit::getType);
 lciowrap.method("getPosition3", [](const EVENT::CalorimeterHit* hit, ArrayRef<double> x)->bool {
     const float* p = hit->getPosition();
-    if (not p) return false;
+    if (not p) {
+        x[0] = nan("");
+        x[1] = nan("");
+        x[2] = nan("");
+        return false;
+    }
     x[0] = p[0];
     x[1] = p[1];
     x[2] = p[2];
@@ -53,7 +63,6 @@ lciowrap.method("_getPosition", [](const EVENT::CalorimeterHit* hit) {
     if (not p) {
         return make_tuple(nanf(""), nanf(""), nanf(""));
     }
-
     return make_tuple(p[0], p[1], p[2]);
 });
 
diff --git a/src/Cluster.icc b/src/Cluster.icc
index 049f946..0ca0780 100644
--- a/src/Cluster.icc
+++ b/src/Cluster.icc
@@ -24,7 +24,12 @@ lciowrap.method("getClusters", [](const EVENT::Cluster* c)->const std::vector<Cl
 
 lciowrap.method("getPosition3", [](const EVENT::Cluster* c, ArrayRef<double> x)->bool {
     const float* p3 = c->getPosition();
-    if (not p3) return false;
+    if (not p3) {
+        x[0] = nan("");
+        x[1] = nan("");
+        x[2] = nan("");
+        return false;
+    }
     x[0] = p3[0];
     x[1] = p3[1];
     x[2] = p3[2];
diff --git a/src/MCParticle.icc b/src/MCParticle.icc
index bb17762..c0ded7f 100644
--- a/src/MCParticle.icc
+++ b/src/MCParticle.icc
@@ -32,7 +32,12 @@ lciowrap.method("getDaughters", [](const EVENT::MCParticle* p)->const std::vecto
 // returns a bool to indicate whether this was a nullptr
 lciowrap.method("getVertex3", [](const EVENT::MCParticle* p, ArrayRef<double> v)->bool {
     const double* vtx = p->getVertex();
-    if (not vtx) return false;
+    if (not vtx) {
+        v[0] = nan("");
+        v[1] = nan("");
+        v[2] = nan("");
+        return false;
+    }
     v[0] = vtx[0];
     v[1] = vtx[1];
     v[2] = vtx[2];
@@ -49,7 +54,12 @@ lciowrap.method("_getVertex", [](const EVENT::MCParticle* p) {
 // returns a bool to indicate whether this was a nullptr
 lciowrap.method("getEndpoint3", [](const EVENT::MCParticle* p, ArrayRef<double> pos)->bool {
     const double* endp = p->getEndpoint();
-    if (not endp) return false;
+    if (not endp) {
+        pos[0] = nan("");
+        pos[1] = nan("");
+        pos[2] = nan("");
+        return false;
+    }
     pos[0] = endp[0];
     pos[1] = endp[1];
     pos[2] = endp[2];
@@ -66,7 +76,12 @@ lciowrap.method("_getEndpoint", [](const EVENT::MCParticle* p) {
 // returns a bool to indicate whether this was a nullptr
 lciowrap.method("getMomentum3", [](const EVENT::MCParticle* p, ArrayRef<double> p3)->bool {
     const double* mom = p->getMomentum();
-    if (not mom) return false;
+    if (not mom) {
+        p3[0] = nan("");
+        p3[1] = nan("");
+        p3[2] = nan("");
+        return false;
+    }
     p3[0] = mom[0];
     p3[1] = mom[1];
     p3[2] = mom[2];
@@ -83,7 +98,12 @@ lciowrap.method("_getMomentum", [](const EVENT::MCParticle* p) {
 // returns a bool to indicate whether this was a nullptr
 lciowrap.method("getMomentumAtEndpoint3", [](const EVENT::MCParticle* p, ArrayRef<double> p3)->bool {
     const double* mom = p->getMomentumAtEndpoint();
-    if (not mom) return false;
+    if (not mom) {
+        p3[0] = nan("");
+        p3[1] = nan("");
+        p3[2] = nan("");
+        return false;
+    }
     p3[0] = mom[0];
     p3[1] = mom[1];
     p3[2] = mom[2];
diff --git a/src/ReconstructedParticle.icc b/src/ReconstructedParticle.icc
index 7bc296d..b1143f6 100644
--- a/src/ReconstructedParticle.icc
+++ b/src/ReconstructedParticle.icc
@@ -16,7 +16,12 @@ lciowrap.add_type<EVENT::ReconstructedParticle>("ReconstructedParticle", jlcxx::
 
 lciowrap.method("getMomentum3", [](const EVENT::ReconstructedParticle* p, ArrayRef<double> mom)->bool {
     const double* p3 = p->getMomentum();
-    if (not p3) return false;
+    if (not p3) {
+        mom[0] = nan("");
+        mom[1] = nan("");
+        mom[2] = nan("");
+        return false;
+    }
     mom[0] = p3[0];
     mom[1] = p3[1];
     mom[2] = p3[2];
@@ -32,7 +37,12 @@ lciowrap.method("_getMomentum", [](const EVENT::ReconstructedParticle* p) {
 
 lciowrap.method("getReferencePoint3", [](const EVENT::ReconstructedParticle* p, ArrayRef<double> point)->bool {
     const float* x = p->getReferencePoint();
-    if (not x) return false;
+    if (not x) {
+        point[0] = nan("");
+        point[1] = nan("");
+        point[2] = nan("");
+        return false;
+    }
     point[0] = x[0];
     point[1] = x[1];
     point[2] = x[2];
diff --git a/src/Track.icc b/src/Track.icc
index 3daf313..af4c889 100644
--- a/src/Track.icc
+++ b/src/Track.icc
@@ -42,7 +42,12 @@ jlcxx::stl::apply_stl<EVENT::TrackState*>(lciowrap);
 
 lciowrap.method("getReferencePoint3", [](const EVENT::TrackState* t, ArrayRef<double> x)->bool {
     const float* p3 = t->getReferencePoint();
-    if (not p3) return false;
+    if (not p3) {
+        x[0] = nan("");
+        x[1] = nan("");
+        x[2] = nan("");
+        return false;
+    }
     x[0] = p3[0];
     x[1] = p3[1];
     x[2] = p3[2];
@@ -78,7 +83,12 @@ jlcxx::stl::apply_stl<EVENT::Track*>(lciowrap);
 
 lciowrap.method("getReferencePoint3", [](const EVENT::Track* t, ArrayRef<double> x)->bool {
     const float* p3 = t->getReferencePoint();
-    if (not p3) return false;
+    if (not p3) {
+        x[0] = nan("");
+        x[1] = nan("");
+        x[2] = nan("");
+        return false;
+    }
     x[0] = p3[0];
     x[1] = p3[1];
     x[2] = p3[2];
diff --git a/src/TrackerHitTypes.icc b/src/TrackerHitTypes.icc
index 6a9b263..d65a373 100644
--- a/src/TrackerHitTypes.icc
+++ b/src/TrackerHitTypes.icc
@@ -17,7 +17,12 @@ jlcxx::stl::apply_stl<EVENT::SimTrackerHit*>(lciowrap);
 // returns a bool to indicate whether this was a nullptr
 lciowrap.method("getPosition3", [](const EVENT::SimTrackerHit* hit, ArrayRef<double> x)->bool {
     const double* p = hit->getPosition();
-    if (not p) return false;
+    if (not p) {
+        x[0] = nan("");
+        x[1] = nan("");
+        x[2] = nan("");
+        return false;
+    }
     x[0] = p[0];
     x[1] = p[1];
     x[2] = p[2];
@@ -34,7 +39,12 @@ lciowrap.method("_getPosition", [](const EVENT::SimTrackerHit* hit) {
 // returns a bool to indicate whether this was a nusllptr
 lciowrap.method("getMomentum3", [](const EVENT::SimTrackerHit* hit, ArrayRef<double> x)->bool {
     const float* p = hit->getMomentum();
-    if (not p) return false;
+    if (not p) {
+        x[0] = nan("");
+        x[1] = nan("");
+        x[2] = nan("");
+        return false;
+    }
     x[0] = p[0];
     x[1] = p[1];
     x[2] = p[2];
@@ -62,7 +72,12 @@ lciowrap.add_type<EVENT::TrackerHit>("TrackerHit", jlcxx::julia_base_type<LCObje
 // returns a bool to indicate whether this was a nullptr
 lciowrap.method("getPosition3", [](const EVENT::TrackerHit* hit, ArrayRef<double> x)->bool {
     const double* p = hit->getPosition();
-    if (not p) return false;
+    if (not p) {
+        x[0] = nan("");
+        x[1] = nan("");
+        x[2] = nan("");
+        return false;
+    }
     x[0] = p[0];
     x[1] = p[1];
     x[2] = p[2];
diff --git a/src/lciowrap.cc b/src/lciowrap.cc
index 2134101..c25c322 100644
--- a/src/lciowrap.cc
+++ b/src/lciowrap.cc
@@ -192,7 +192,12 @@ JLCXX_MODULE define_julia_module(jlcxx::Module& lciowrap)
         .method("getParameters", &Vertex::getParameters);
     lciowrap.method("getPosition3", [](const Vertex* v, ArrayRef<double> x)->bool {
         const float* p3 = v->getPosition();
-        if (not p3) return false;
+        if (not p3) {
+            x[0] = nan("");
+            x[1] = nan("");
+            x[2] = nan("");
+            return false;
+        }
         x[0] = p3[0];
         x[1] = p3[1];
         x[2] = p3[2];