Changeset 14008 for trunk/sources/HeuristicLab.Visualization.ChartControlsExtensions/3.3/ChartUtil.cs

Timestamp:

07/06/16 14:50:17 (8 years ago)

Author:

bburlacu

Message:

#2594: Added chart util method to calculate the "optimal" axis interval (reducing the number of fractional digits to make it look nice). Modified the regression solution line chart and scatter plot to use the new scaling method.

File:

• trunk/sources/HeuristicLab.Visualization.ChartControlsExtensions/3.3/ChartUtil.cs (modified) (2 diffs)

trunk/sources/HeuristicLab.Visualization.ChartControlsExtensions/3.3/ChartUtil.cs

@@ -43 +43 @@
     }
 
+    // this method tries to find an axis interval with as few fractional digits as possible (because it looks nicer)
+    // we only try between 3 and 5 ticks (inclusive) because it wouldn't make sense to exceed this interval
+    public static void CalculateOptimalAxisInterval(double min, double max, out double axisMin, out double axisMax, out double axisInterval) {
+      CalculateAxisInterval(min, max, 5, out axisMin, out axisMax, out axisInterval);
+      int bestLsp = int.MaxValue;
+      for (int ticks = 3; ticks <= 5; ++ticks) {
+        double aMin, aMax, aInterval;
+        CalculateAxisInterval(min, max, ticks, out aMin, out aMax, out aInterval);
+        var x = aInterval;
+        int lsp = 0; // position of the least significant fractional digit
+        while (x - Math.Floor(x) > 0) {
+          ++lsp;
+          x *= 10;
+        }
+        if (lsp <= bestLsp) {
+          axisMin = aMin;
+          axisMax = aMax;
+          axisInterval = aInterval;
+          bestLsp = lsp;
+        }
+      }
+    }
+
     private static int Decimals(this double x) {
       if (x.IsAlmost(0) || double.IsInfinity(x) || double.IsNaN(x))
@@ -48 +71 @@
 
       var v = Math.Abs(x);
-      int d = 0;
+      int d = 1;
       while (v < 1) {
         v *= 10;