diff --git a/NPLib/Detectors/Hira/THiraPhysics.cxx b/NPLib/Detectors/Hira/THiraPhysics.cxx
index 4ee9b79b60f928983501e174f93afd3780d132e3..6c6e50a7ab142b90130bb2ecc8d41faa5f61646e 100644
--- a/NPLib/Detectors/Hira/THiraPhysics.cxx
+++ b/NPLib/Detectors/Hira/THiraPhysics.cxx
@@ -33,7 +33,7 @@
 #include <fstream>
 #include <limits>
 #include <stdlib.h>
-#include <tgmath.h>
+#include <cgmath>
 using namespace std;
 
 //   ROOT