src/GUI/cadencegraph.cpp

@@ -47,7 +47,7 @@ QList<GraphItem*> CadenceGraph::loadData(const Data &data)
 		const Track &track = data.tracks().at(i);
 		const Graph &graph = track.cadence();
 
-		if (graph.isEmpty()) {
+		if (!graph.isValid()) {
 			_palette.nextColor();
 			graphs.append(0);
 		} else {

src/GUI/elevationgraph.cpp

@@ -85,7 +85,7 @@ void ElevationGraph::setInfo()
 GraphItem *ElevationGraph::loadGraph(const Graph &graph, PathType type,
   const QColor &color, bool primary)
 {
-	if (graph.isEmpty())
+	if (!graph.isValid())
 		return 0;
 
 	ElevationGraphItem *gi = new ElevationGraphItem(graph, _graphType, _width,

src/GUI/gearratiograph.cpp

@@ -50,7 +50,7 @@ QList<GraphItem*> GearRatioGraph::loadData(const Data &data)
 	for (int i = 0; i < data.tracks().count(); i++) {
 		const Graph &graph = data.tracks().at(i).ratio();
 
-		if (graph.isEmpty()) {
+		if (!graph.isValid()) {
 			_palette.nextColor();
 			graphs.append(0);
 		} else {

src/GUI/graphitem.cpp

@@ -8,6 +8,8 @@ GraphItem::GraphItem(const Graph &graph, GraphType type, int width,
   const QColor &color, Qt::PenStyle style, QGraphicsItem *parent)
   : GraphicsItem(parent), _graph(graph), _type(type), _secondaryGraph(0)
 {
+	Q_ASSERT(_graph.isValid());
+
 	_units = Metric;
 	_sx = 0; _sy = 0;
 	_color = color;

src/GUI/heartrategraph.cpp

@@ -47,7 +47,7 @@ QList<GraphItem*> HeartRateGraph::loadData(const Data &data)
 		const Track &track = data.tracks().at(i);
 		const Graph &graph = track.heartRate();
 
-		if (graph.isEmpty()) {
+		if (!graph.isValid()) {
 			_palette.nextColor();
 			graphs.append(0);
 		} else {

src/GUI/powergraph.cpp

@@ -47,7 +47,7 @@ QList<GraphItem*> PowerGraph::loadData(const Data &data)
 		const Track &track = data.tracks().at(i);
 		const Graph &graph = track.power();
 
-		if (graph.isEmpty()) {
+		if (!graph.isValid()) {
 			_palette.nextColor();
 			graphs.append(0);
 		} else {

src/GUI/speedgraph.cpp

@@ -50,7 +50,7 @@ void SpeedGraph::setInfo()
 GraphItem *SpeedGraph::loadGraph(const Graph &graph, const Track &track,
   const QColor &color, bool primary)
 {
-	if (graph.isEmpty())
+	if (!graph.isValid())
 		return 0;
 
 	SpeedGraphItem *gi = new SpeedGraphItem(graph, _graphType, _width,

src/GUI/temperaturegraph.cpp

@@ -51,7 +51,7 @@ QList<GraphItem*> TemperatureGraph::loadData(const Data &data)
 		const Track &track = data.tracks().at(i);
 		const Graph &graph = track.temperature();
 
-		if (graph.isEmpty()) {
+		if (!graph.isValid()) {
 			_palette.nextColor();
 			graphs.append(0);
 		} else {

src/data/graph.h

@@ -46,6 +46,16 @@ typedef QVector<GraphPoint> GraphSegment;
 class Graph : public QList<GraphSegment>
 {
 public:
+	bool isValid() const
+	{
+		if (isEmpty())
+			return false;
+		for (int i = 0; i < size(); i++)
+			if (at(i).size() < 2)
+				return false;
+		return true;
+	}
+
 	bool hasTime() const
 	{
 		for (int i = 0; i < size(); i++) {

src/data/route.cpp

@@ -68,14 +68,16 @@ GraphPair Route::elevation() const
 {
 	if (_useDEM) {
 		Graph dem(demElevation());
-		return (dem.isEmpty())
-		  ? GraphPair(gpsElevation(), Graph())
-		  : GraphPair(dem, _show2ndElevation ? gpsElevation() : Graph());
+		if (dem.isValid())
+			return GraphPair(dem, _show2ndElevation ? gpsElevation() : Graph());
+		else
+			return GraphPair(gpsElevation(), Graph());
 	} else {
 		Graph gps(gpsElevation());
-		return (gps.isEmpty())
-		  ? GraphPair(demElevation(), Graph())
-		  : GraphPair(gps, _show2ndElevation ? demElevation() : Graph());
+		if (gps.isValid())
+			return GraphPair(gps, _show2ndElevation ? demElevation() : Graph());
+		else
+			return GraphPair(demElevation(), Graph());
 	}
 }
 

src/data/track.cpp

@@ -266,8 +266,7 @@ Graph Track::gpsElevation() const
 			  sd.at(j).elevation()));
 		}
 
-		if (gs.size() >= 2)
-			ret.append(filter(gs, _elevationWindow));
+		ret.append(filter(gs, _elevationWindow));
 	}
 
 	if (_data.style().color().isValid())
@@ -294,8 +293,7 @@ Graph Track::demElevation() const
 			gs.append(GraphPoint(seg.distance.at(j), seg.time.at(j), dem));
 		}
 
-		if (gs.size() >= 2)
-			ret.append(filter(gs, _elevationWindow));
+		ret.append(filter(gs, _elevationWindow));
 	}
 
 	if (_data.style().color().isValid())
@@ -308,14 +306,16 @@ GraphPair Track::elevation() const
 {
 	if (_useDEM) {
 		Graph dem(demElevation());
-		return (dem.isEmpty())
-		  ? GraphPair(gpsElevation(), Graph())
-		  : GraphPair(dem, _show2ndElevation ? gpsElevation() : Graph());
+		if (dem.isValid())
+			return GraphPair(dem, _show2ndElevation ? gpsElevation() : Graph());
+		else
+			return GraphPair(gpsElevation(), Graph());
 	} else {
 		Graph gps(gpsElevation());
-		return (gps.isEmpty())
-		  ? GraphPair(demElevation(), Graph())
-		  : GraphPair(gps, _show2ndElevation ? demElevation() : Graph());
+		if (gps.isValid())
+			return GraphPair(gps, _show2ndElevation ? demElevation() : Graph());
+		else
+			return GraphPair(demElevation(), Graph());
 	}
 }
 
@@ -344,13 +344,11 @@ Graph Track::computedSpeed() const
 			gs.append(GraphPoint(seg.distance.at(j), seg.time.at(j), v));
 		}
 
-		if (gs.size() >= 2) {
-			ret.append(filter(gs, _speedWindow));
-			GraphSegment &filtered = ret.last();
+		ret.append(filter(gs, _speedWindow));
+		GraphSegment &filtered = ret.last();
 
-			for (int j = 0; j < stop.size(); j++)
-				filtered[stop.at(j)].setY(0);
-		}
+		for (int j = 0; j < stop.size(); j++)
+			filtered[stop.at(j)].setY(0);
 	}
 
 	if (_data.style().color().isValid())
@@ -384,13 +382,11 @@ Graph Track::reportedSpeed() const
 			gs.append(GraphPoint(seg.distance.at(j), seg.time.at(j), v));
 		}
 
-		if (gs.size() >= 2) {
-			ret.append(filter(gs, _speedWindow));
-			GraphSegment &filtered = ret.last();
+		ret.append(filter(gs, _speedWindow));
+		GraphSegment &filtered = ret.last();
 
-			for (int j = 0; j < stop.size(); j++)
-				filtered[stop.at(j)].setY(0);
-		}
+		for (int j = 0; j < stop.size(); j++)
+			filtered[stop.at(j)].setY(0);
 	}
 
 	if (_data.style().color().isValid())
@@ -403,14 +399,18 @@ GraphPair Track::speed() const
 {
 	if (_useReportedSpeed) {
 		Graph reported(reportedSpeed());
-		return (reported.isEmpty())
-		  ? GraphPair(computedSpeed(), Graph())
-		  : GraphPair(reported, _show2ndSpeed ? computedSpeed() : Graph());
+		if (reported.isValid())
+			return GraphPair(reported, _show2ndSpeed ? computedSpeed()
+			  : Graph());
+		else
+			return GraphPair(computedSpeed(), Graph());
 	} else {
 		Graph computed(computedSpeed());
-		return (computed.isEmpty())
-		  ? GraphPair(reportedSpeed(), Graph())
-		  : GraphPair(computed, _show2ndSpeed ? reportedSpeed() : Graph());
+		if (computed.isValid())
+			return GraphPair(computed, _show2ndSpeed ? reportedSpeed()
+			  : Graph());
+		else
+			return GraphPair(reportedSpeed(), Graph());
 	}
 }
 
@@ -430,8 +430,7 @@ Graph Track::heartRate() const
 				gs.append(GraphPoint(seg.distance.at(j), seg.time.at(j),
 				  sd.at(j).heartRate()));
 
-		if (gs.size() >= 2)
-			ret.append(filter(gs, _heartRateWindow));
+		ret.append(filter(gs, _heartRateWindow));
 	}
 
 	if (_data.style().color().isValid())
@@ -457,8 +456,7 @@ Graph Track::temperature() const
 				  sd.at(j).temperature()));
 		}
 
-		if (gs.size() >= 2)
-			ret.append(gs);
+		ret.append(gs);
 	}
 
 	if (_data.style().color().isValid())
@@ -483,8 +481,7 @@ Graph Track::ratio() const
 				gs.append(GraphPoint(seg.distance.at(j), seg.time.at(j),
 				  sd.at(j).ratio()));
 
-		if (gs.size() >= 2)
-			ret.append(gs);
+		ret.append(gs);
 	}
 
 	if (_data.style().color().isValid())
@@ -518,13 +515,11 @@ Graph Track::cadence() const
 			gs.append(GraphPoint(seg.distance.at(j), seg.time.at(j), c));
 		}
 
-		if (gs.size() >= 2) {
-			ret.append(filter(gs, _cadenceWindow));
-			GraphSegment &filtered = ret.last();
+		ret.append(filter(gs, _cadenceWindow));
+		GraphSegment &filtered = ret.last();
 
-			for (int j = 0; j < stop.size(); j++)
-				filtered[stop.at(j)].setY(0);
-		}
+		for (int j = 0; j < stop.size(); j++)
+			filtered[stop.at(j)].setY(0);
 	}
 
 	if (_data.style().color().isValid())
@@ -559,13 +554,11 @@ Graph Track::power() const
 			gs.append(GraphPoint(seg.distance.at(j), seg.time.at(j), p));
 		}
 
-		if (gs.size() >= 2) {
-			ret.append(filter(gs, _powerWindow));
-			GraphSegment &filtered = ret.last();
+		ret.append(filter(gs, _powerWindow));
+		GraphSegment &filtered = ret.last();
 
-			for (int j = 0; j < stop.size(); j++)
-				filtered[stop.at(j)].setY(0);
-		}
+		for (int j = 0; j < stop.size(); j++)
+			filtered[stop.at(j)].setY(0);
 	}
 
 	if (_data.style().color().isValid())