From e4a4427991f004870b49d6c77134a0b08e785265 Mon Sep 17 00:00:00 2001
From: Paul Riseborough <p_riseborough@live.com.au>
Date: Fri, 10 Mar 2017 07:36:56 +1100
Subject: [PATCH] Revert "EKF: fix compile error"

This reverts commit 6db552717deefff6b4ad7078bcf4c769d94f1957.
---
 EKF/ekf_helper.cpp | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/EKF/ekf_helper.cpp b/EKF/ekf_helper.cpp
index 12ec0a9d2e..5f22cdf25a 100644
--- a/EKF/ekf_helper.cpp
+++ b/EKF/ekf_helper.cpp
@@ -42,6 +42,8 @@
 #include "ekf.h"
 #include "mathlib.h"
 
+using std::abs;
+
 // Reset the velocity states. If we have a recent and valid
 // gps measurement then use for velocity initialisation
 bool Ekf::resetVelocity()