From c1791b34389e318d5ff3a07f8be93de759d998cf Mon Sep 17 00:00:00 2001
From: Mark Liversedge <liversedge@gmail.com>
Date: Fri, 1 Nov 2013 16:47:15 +0000
Subject: [PATCH] Fix W' calculator for bad data

Fix 1s smoothing to ensure time doesn't go backwards
as when the same timestamp is used more than once the
QwtSpline used to interpolate returns all zeroes.
---
 src/WPrime.cpp | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/src/WPrime.cpp b/src/WPrime.cpp
index fa8b0c36a..901456c78 100644
--- a/src/WPrime.cpp
+++ b/src/WPrime.cpp
@@ -71,9 +71,16 @@ WPrime::setRide(RideFile *input)
     // create a raw time series in the format QwtSpline wants
     QVector<QPointF> points;
     int last=0;
+    RideFilePoint *lp=NULL;
     foreach(RideFilePoint *p, input->dataPoints()) {
-        points << QPointF(p->secs, p->watts);
+
+        // lets not go backwards -- or two sampls at the same time
+        if ((lp && p->secs > lp->secs) || !lp)
+            points << QPointF(p->secs, p->watts);
+
+        // update state
         last = p->secs;
+        lp = p;
     }
 
     // Create a spline