From 4a5a8d59feca4b6fc065b42954d80844fe27fe69 Mon Sep 17 00:00:00 2001
From: Matthias Grob <maetugr@gmail.com>
Date: Mon, 21 Mar 2022 15:58:08 +0100
Subject: [PATCH] matrix helper: add documentation for sign function

---
 src/lib/matrix/matrix/helper_functions.hpp | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/lib/matrix/matrix/helper_functions.hpp b/src/lib/matrix/matrix/helper_functions.hpp
index b1e0890407..7426fdcf57 100644
--- a/src/lib/matrix/matrix/helper_functions.hpp
+++ b/src/lib/matrix/matrix/helper_functions.hpp
@@ -152,6 +152,12 @@ Type unwrap_pi(const Type last_angle, const Type new_angle)
 	return unwrap(last_angle, new_angle, Type(-M_PI), Type(M_PI));
 }
 
+/**
+ * Type-safe sign/signum function
+ *
+ * @param[in] val Number to take the sign from
+ * @return -1 if val < 0, 0 if val == 0, 1 if val > 0
+ */
 template<typename T>
 int sign(T val)
 {