diff --git a/libraries/AP_Math/AP_Math.cpp b/libraries/AP_Math/AP_Math.cpp
index 20e49f9264..087aedff99 100644
--- a/libraries/AP_Math/AP_Math.cpp
+++ b/libraries/AP_Math/AP_Math.cpp
@@ -117,3 +117,12 @@ float pythagorous2(float a, float b) {
 float pythagorous3(float a, float b, float c) {
 	return sqrtf(sq(a)+sq(b)+sq(c));
 }
+
+float maxf(float a, float b)
+{
+    return (a>b?a:b);
+}
+float minf(float a, float b)
+{
+    return (a<b?a:b);
+}
diff --git a/libraries/AP_Math/AP_Math.h b/libraries/AP_Math/AP_Math.h
index 7a9011bbb3..043a443bd0 100644
--- a/libraries/AP_Math/AP_Math.h
+++ b/libraries/AP_Math/AP_Math.h
@@ -193,6 +193,8 @@ float pythagorous3(float a, float b, float c);
 #define max(a,b) ((a)>(b)?(a):(b))
 #define min(a,b) ((a)<(b)?(a):(b))
 
+float maxf(float a, float b);
+float minf(float a, float b);
 
 #endif // AP_MATH_H