logarithmic axis bar charts

xchart/src/main/java/com/xeiam/xchart/internal/chartpart/AxisTickCalculator.java

@@ -27,6 +27,7 @@ import java.util.List;
 
 import com.xeiam.xchart.StyleManager;
 import com.xeiam.xchart.StyleManager.ChartType;
+import com.xeiam.xchart.internal.Utils;
 import com.xeiam.xchart.internal.chartpart.Axis.Direction;
 
 /**
@@ -78,6 +79,12 @@ public abstract class AxisTickCalculator {
         overrideMaxValue = BigDecimal.ZERO;
       }
     }
+
+    if (styleManager.getChartType() == ChartType.Bar && styleManager.isYAxisLogarithmic()) {
+      int logMin = (int) Math.floor(Math.log10(minValue.doubleValue()));
+      overrideMinValue = new BigDecimal(Utils.pow(10, logMin).doubleValue());
+    }
+
     // override min and maxValue if specified
     if (axisDirection == Direction.X && styleManager.getXAxisMin() != null) {
       overrideMinValue = new BigDecimal(styleManager.getXAxisMin());
@@ -91,23 +98,14 @@ public abstract class AxisTickCalculator {
     if (axisDirection == Direction.Y && styleManager.getYAxisMax() != null) {
       overrideMaxValue = new BigDecimal(styleManager.getYAxisMax());
     }
-
     this.axisDirection = axisDirection;
     this.workingSpace = workingSpace;
     this.minValue = overrideMinValue;
+    // this.minValue = new BigDecimal(10000);
     this.maxValue = overrideMaxValue;
     this.styleManager = styleManager;
   }
 
-  BigDecimal pow(double base, int exponent) {
-
-    if (exponent > 0) {
-      return new BigDecimal(base).pow(exponent);
-    } else {
-      return BigDecimal.ONE.divide(new BigDecimal(base).pow(-exponent));
-    }
-  }
-
   BigDecimal getFirstPosition(BigDecimal gridStep) {
 
     BigDecimal firstPosition;

xchart/src/main/java/com/xeiam/xchart/internal/chartpart/AxisTickLogarithmicCalculator.java

@@ -24,6 +24,7 @@ package com.xeiam.xchart.internal.chartpart;
 import java.math.BigDecimal;
 
 import com.xeiam.xchart.StyleManager;
+import com.xeiam.xchart.internal.Utils;
 import com.xeiam.xchart.internal.chartpart.Axis.Direction;
 
 /**
@@ -90,8 +91,8 @@ public class AxisTickLogarithmicCalculator extends AxisTickCalculator {
 
     // BigDecimal firstPosition = getFirstPosition(tickStep);
     // System.out.println("firstPosition: " + firstPosition);
-    BigDecimal firstPosition = pow(10, logMin);
-    BigDecimal tickStep = pow(10, logMin - 1);
+    BigDecimal firstPosition = Utils.pow(10, logMin);
+    BigDecimal tickStep = Utils.pow(10, logMin - 1);
 
     for (int i = logMin; i <= logMax; i++) { // for each decade
 
@@ -100,7 +101,7 @@ public class AxisTickLogarithmicCalculator extends AxisTickCalculator {
       // System.out.println("i: " + i);
       // System.out.println("pow(10, i).doubleValue(): " + pow(10, i).doubleValue());
 
-      for (BigDecimal j = firstPosition; j.doubleValue() <= pow(10, i).doubleValue(); j = j.add(tickStep)) {
+      for (BigDecimal j = firstPosition; j.doubleValue() <= Utils.pow(10, i).doubleValue(); j = j.add(tickStep)) {
 
         // System.out.println("j: " + j);
         // System.out.println(Math.log10(j.doubleValue()) % 1);
@@ -127,8 +128,8 @@ public class AxisTickLogarithmicCalculator extends AxisTickCalculator {
             * tickSpace);
         tickLocations.add(tickLabelPosition);
       }
-      tickStep = tickStep.multiply(pow(10, 1));
-      firstPosition = tickStep.add(pow(10, i));
+      tickStep = tickStep.multiply(Utils.pow(10, 1));
+      firstPosition = tickStep.add(Utils.pow(10, i));
     }
   }
 }

xchart/src/main/java/com/xeiam/xchart/internal/chartpart/AxisTickNumericalCalculator.java

@@ -24,6 +24,7 @@ package com.xeiam.xchart.internal.chartpart;
 import java.math.BigDecimal;
 
 import com.xeiam.xchart.StyleManager;
+import com.xeiam.xchart.internal.Utils;
 import com.xeiam.xchart.internal.chartpart.Axis.Direction;
 
 /**
@@ -121,16 +122,16 @@ public class AxisTickNumericalCalculator extends AxisTickCalculator {
     BigDecimal gridStep;
     if (significand > 7.5) {
       // gridStep = 10.0 * 10 ** exponent
-      gridStep = BigDecimal.TEN.multiply(pow(10, exponent));
+      gridStep = BigDecimal.TEN.multiply(Utils.pow(10, exponent));
     } else if (significand > 3.5) {
       // gridStep = 5.0 * 10 ** exponent
-      gridStep = new BigDecimal(new Double(5).toString()).multiply(pow(10, exponent));
+      gridStep = new BigDecimal(new Double(5).toString()).multiply(Utils.pow(10, exponent));
     } else if (significand > 1.5) {
       // gridStep = 2.0 * 10 ** exponent
-      gridStep = new BigDecimal(new Double(2).toString()).multiply(pow(10, exponent));
+      gridStep = new BigDecimal(new Double(2).toString()).multiply(Utils.pow(10, exponent));
     } else {
       // gridStep = 1.0 * 10 ** exponent
-      gridStep = pow(10, exponent);
+      gridStep = Utils.pow(10, exponent);
     }
     return gridStep;
   }

xchart/src/main/java/com/xeiam/xchart/internal/chartpart/PlotContentBarChart.java

@@ -93,11 +93,20 @@ public class PlotContentBarChart extends PlotContent {
       // override min and maxValue if specified
       if (getChartPainter().getStyleManager().getYAxisMin() != null) {
         yMin = new BigDecimal(getChartPainter().getStyleManager().getYAxisMin());
+      } else if (getChartPainter().getStyleManager().isYAxisLogarithmic()) {
+        // int logMin = (int) Math.floor(Math.log10(getChartPainter().getAxisPair().getyAxis().getMin().doubleValue()));
+        int logMin = (int) Math.floor(Math.log10(getChartPainter().getAxisPair().getyAxis().getMin().doubleValue()));
+        // System.out.println("logMin: " + logMin);
+        // System.out.println("min : " + getChartPainter().getAxisPair().getyAxis().getMin().doubleValue());
+        // yMin = new BigDecimal(Math.log10(Utils.pow(10, logMin).doubleValue()));
+        // yMin = new BigDecimal(Utils.pow(10, logMin).doubleValue());
+        yMin = new BigDecimal(logMin);
       }
       if (getChartPainter().getStyleManager().getYAxisMax() != null) {
         yMax = new BigDecimal(getChartPainter().getStyleManager().getYAxisMax());
+      } else if (getChartPainter().getStyleManager().isYAxisLogarithmic()) {
+        yMax = new BigDecimal(Math.log10(yMax.doubleValue()));
       }
-
       // figure out the general form of the chart
       int chartForm = 1; // 1=positive, -1=negative, 0=span
       if (yMin.compareTo(BigDecimal.ZERO) > 0 && yMax.compareTo(BigDecimal.ZERO) > 0) {
@@ -107,6 +116,8 @@ public class PlotContentBarChart extends PlotContent {
       } else {
         chartForm = 0;// span chart
       }
+      // System.out.println(yMin);
+      // System.out.println(yMax);
 
       Iterator<?> categoryItr = categories.iterator();
       Iterator<Number> yItr = yData.iterator();
@@ -117,6 +128,11 @@ public class PlotContentBarChart extends PlotContent {
         if (xData.contains(categoryItr.next())) {
 
           BigDecimal y = new BigDecimal(yItr.next().doubleValue());
+          if (getChartPainter().getStyleManager().isYAxisLogarithmic()) {
+            y = new BigDecimal(Math.log10(y.doubleValue()));
+          } else {
+            y = new BigDecimal(y.doubleValue());
+          }
           BigDecimal yTop = null;
           BigDecimal yBottom = null;
 
@@ -142,15 +158,10 @@ public class PlotContentBarChart extends PlotContent {
             break;
           }
 
-          // if (yTop.compareTo(yMax) > 0) {
-          // yTop = yMax;
-          // }
           int yTransform = (int) (bounds.getHeight() - (yTopMargin + yTop.subtract(yMin).doubleValue() / yMax.subtract(yMin).doubleValue() * yTickSpace));
+
           int yOffset = (int) (bounds.getY() + yTransform) + 1;
 
-          // if (yBottom.compareTo(yMin) > 0) {
-          // yBottom = yMin;
-          // }
           int zeroTransform = (int) (bounds.getHeight() - (yTopMargin + (yBottom.subtract(yMin).doubleValue()) / (yMax.subtract(yMin).doubleValue()) * yTickSpace));
           int zeroOffset = (int) (bounds.getY() + zeroTransform) + 1;