EKF: Use ecl::powf in comparison test

EKF/python/ekf_derivation/generated/util.h

@@ -0,0 +1,24 @@
+#include "../../../../../matrix/matrix/math.hpp"
+
+typedef matrix::SquareMatrix<float, 24> SquareMatrix24f;
+
+inline float sq(float in) {
+    return in * in;
+}
+
+namespace ecl{
+	inline float powf(float x, int exp)
+	{
+		float ret;
+		if (exp > 0) {
+			ret = x;
+			for (int count = 1; count < exp; count++) {
+				ret *= x;
+			}
+			return ret;
+		} else if (exp < 0) {
+			return 1.0f / ecl::powf(x, -exp);
+		}
+		return 1.0f;
+	}
+}