fix radar chart negative value rendering bug if startAtZeroEnabled is…

… false for issue ChartsOrg#166
liuxuan30 · Aug 12, 2015 · f76aae9 · f76aae9
1 parent 78e5df8
commit f76aae9
Showing 1 changed file with 13 additions and 1 deletion.
diff --git a/Charts/Classes/Renderers/ChartYAxisRendererRadarChart.swift b/Charts/Classes/Renderers/ChartYAxisRendererRadarChart.swift
@@ -96,7 +96,17 @@ public class ChartYAxisRendererRadarChart: ChartYAxisRenderer
             }
             else
             {
-                var first = ceil(Double(yMin) / interval) * interval
+                var rawValue = Double(yMin) / interval
+                var first: Double;
+                // if raw value negative, we need to use floor rather than ceil
+                if (rawValue < 0)
+                {
+                    first = floor(rawValue) * interval
+                }
+                else
+                {
+                    first = ceil(Double(yMin) / interval) * interval
+                }
 
                 if (first == 0.0)
                 { // Fix for IEEE negative zero case (Where value == -0.0, and 0.0 == -0.0)
@@ -132,6 +142,8 @@ public class ChartYAxisRendererRadarChart: ChartYAxisRenderer
         }
 
         _yAxis.axisMaximum = _yAxis.entries[_yAxis.entryCount - 1]
+        // set axisMinimum to be the minimum value.
+        _yAxis.axisMinimum = _yAxis.entries[0]
         _yAxis.axisRange = abs(_yAxis.axisMaximum - _yAxis.axisMinimum)
     }