diff --git a/matrix/helper_functions.hpp b/matrix/helper_functions.hpp
index d42d0c949a..db23bc576a 100644
--- a/matrix/helper_functions.hpp
+++ b/matrix/helper_functions.hpp
@@ -10,7 +10,7 @@ namespace matrix
 template<typename Type>
 Type wrap_pi(Type x)
 {
-    if (!isfinite(x)) {
+    if (!isfinite(float(x))) {
         return x;
     }