add lactate-ramp plot for activities and activity-comparison

lactate-ramp.py

@@ -0,0 +1,31 @@
+metrics = GC.activityMetrics(compare=True)
+n_activities = len(metrics)
+
+GC.setChart(title='Lactate-Ramp',
+            type=GC.CHART_LINE,
+            animate=False,
+            legpos=GC_ALIGN_TOP,
+            stack=False)
+
+for i, metric in enumerate(metrics):
+    date = metric[0]['date']
+    color = metric[1]
+    print(color)
+    x = list(GC.xdataSeries('Lactate-Ramp', 'Power', compareindex=i))
+    y = list(GC.xdataSeries('Lactate-Ramp', 'Lactate', compareindex=i))
+    if not (x and y):
+        continue
+    GC.addCurve(name=str(date),
+                x=x,
+                y=y,
+                xaxis='Power',
+                yaxis='Lactate',
+                color=color,
+                line=GC_LINE_SOLID,
+                symbol=GC_SYMBOL_CIRCLE,
+                size=3,
+                opacity=100,
+                opengl=False)
+
+GC.setAxis('Power', min=90, max=350, type=GC.AXIS_CONTINUOUS)
+GC.setAxis('Lactate', min=0.0, max=10.0, type=GC.AXIS_CONTINUOUS)