added histogram demo charts

xchart-demo/src/main/java/com/xeiam/xchart/demo/XChartDemo.java

@@ -38,6 +38,8 @@ import com.xeiam.xchart.demo.charts.bar.BarChart02;
 import com.xeiam.xchart.demo.charts.bar.BarChart03;
 import com.xeiam.xchart.demo.charts.bar.BarChart04;
 import com.xeiam.xchart.demo.charts.bar.BarChart05;
+import com.xeiam.xchart.demo.charts.bar.BarChart06;
+import com.xeiam.xchart.demo.charts.bar.BarChart07;
 import com.xeiam.xchart.demo.charts.date.DateChart01;
 import com.xeiam.xchart.demo.charts.date.DateChart02;
 import com.xeiam.xchart.demo.charts.date.DateChart03;
@@ -192,7 +194,7 @@ public class XChartDemo extends JPanel implements TreeSelectionListener {
     defaultMutableTreeNode = new DefaultMutableTreeNode(new ChartInfo("AreaChart02 - Null Y-Axis Data Points", new AreaChart02().getChart()));
     category.add(defaultMutableTreeNode);
 
-    // First category
+    // Line category
     category = new DefaultMutableTreeNode("Line Charts");
     top.add(category);
 
@@ -249,6 +251,12 @@ public class XChartDemo extends JPanel implements TreeSelectionListener {
     defaultMutableTreeNode = new DefaultMutableTreeNode(new ChartInfo("BarChart05 - GGPlot2 Theme", new BarChart05().getChart()));
     category.add(defaultMutableTreeNode);
 
+    defaultMutableTreeNode = new DefaultMutableTreeNode(new ChartInfo("BarChart06 - Histogram Overlapped", new BarChart06().getChart()));
+    category.add(defaultMutableTreeNode);
+
+    defaultMutableTreeNode = new DefaultMutableTreeNode(new ChartInfo("BarChart07 - Histogram Not Overlapped", new BarChart07().getChart()));
+    category.add(defaultMutableTreeNode);
+
     // Theme category
     category = new DefaultMutableTreeNode("Chart Themes");
     top.add(category);

xchart-demo/src/main/java/com/xeiam/xchart/demo/charts/bar/BarChart06.java

@@ -21,17 +21,19 @@ import java.util.Random;
 
 import com.xeiam.xchart.Chart;
 import com.xeiam.xchart.ChartBuilder;
+import com.xeiam.xchart.Histogram;
 import com.xeiam.xchart.StyleManager.ChartType;
 import com.xeiam.xchart.StyleManager.LegendPosition;
 import com.xeiam.xchart.SwingWrapper;
 import com.xeiam.xchart.demo.charts.ExampleChart;
 
 /**
- * Basic Bar Chart
+ * Histogram Overlapped
  * <p>
  * Demonstrates the following:
  * <ul>
  * <li>Histogram
+ * <li>Bar Chart styles - overlapped, bar width
  */
 public class BarChart06 implements ExampleChart {
 
@@ -46,15 +48,18 @@ public class BarChart06 implements ExampleChart {
   public Chart getChart() {
 
     // Create Chart
-    Chart chart = new ChartBuilder().chartType(ChartType.Bar).width(800).height(600).title("Score Histogram").xAxisTitle("Score").yAxisTitle("Count").build();
+    Chart chart = new ChartBuilder().chartType(ChartType.Bar).width(800).height(600).title("Score Histogram").xAxisTitle("Mean").yAxisTitle("Count").build();
 
-    chart.addSeries("histogram 1", getGaussianData(10000), 30, -30, 30);
-    chart.addSeries("histogram 2", getGaussianData(5000), 30, -30, 30);
+    Histogram histogram1 = new Histogram(getGaussianData(10000), 30, -30, 30);
+    Histogram histogram2 = new Histogram(getGaussianData(5000), 30, -30, 30);
+    chart.addSeries("histogram 1", histogram1.getxAxisData(), histogram1.getyAxisData());
+    chart.addSeries("histogram 2", histogram2.getxAxisData(), histogram2.getyAxisData());
 
     // Customize Chart
     chart.getStyleManager().setLegendPosition(LegendPosition.InsideNW);
     chart.getStyleManager().setBarWidthPercentage(.96);
-    chart.getStyleManager().setOverlapped(false);
+    chart.getStyleManager().setOverlapped(true);
+
     return chart;
   }
 

xchart-demo/src/main/java/com/xeiam/xchart/demo/charts/bar/BarChart07.java

+/**
+ * Copyright 2011 - 2014 Xeiam LLC.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.xeiam.xchart.demo.charts.bar;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Random;
+
+import com.xeiam.xchart.Chart;
+import com.xeiam.xchart.ChartBuilder;
+import com.xeiam.xchart.Histogram;
+import com.xeiam.xchart.StyleManager.ChartType;
+import com.xeiam.xchart.StyleManager.LegendPosition;
+import com.xeiam.xchart.SwingWrapper;
+import com.xeiam.xchart.demo.charts.ExampleChart;
+
+/**
+ * Histogram Not Overlapped
+ * <p>
+ * Demonstrates the following:
+ * <ul>
+ * <li>Histogram
+ * <li>Bar Chart styles - not overlapped, bar width
+ * <li>Integer data values
+ */
+public class BarChart07 implements ExampleChart {
+
+  public static void main(String[] args) {
+
+    ExampleChart exampleChart = new BarChart07();
+    Chart chart = exampleChart.getChart();
+    new SwingWrapper(chart).displayChart();
+  }
+
+  @Override
+  public Chart getChart() {
+
+    // Create Chart
+    Chart chart = new ChartBuilder().chartType(ChartType.Bar).width(800).height(600).title("Score Histogram").xAxisTitle("Mean").yAxisTitle("Count").build();
+
+    Histogram histogram1 = new Histogram(getGaussianData(1000), 10, -30, 30);
+    chart.addSeries("histogram 1", histogram1.getxAxisData(), histogram1.getyAxisData());
+    Histogram histogram2 = new Histogram(getGaussianData(1000), 10, -30, 30);
+    chart.addSeries("histogram 2", histogram2.getxAxisData(), histogram2.getyAxisData());
+
+    // Customize Chart
+    chart.getStyleManager().setLegendPosition(LegendPosition.InsideNW);
+    chart.getStyleManager().setBarWidthPercentage(.96);
+
+    return chart;
+  }
+
+  private List<Integer> getGaussianData(int count) {
+
+    List<Integer> data = new ArrayList<Integer>(count);
+    Random r = new Random();
+    for (int i = 0; i < count; i++) {
+      data.add((int) (r.nextGaussian() * 10));
+      // data.add(r.nextDouble() * 60 - 30);
+    }
+    return data;
+  }
+
+}

xchart/src/main/java/com/xeiam/xchart/Chart.java

@@ -22,7 +22,6 @@ import java.util.List;
 import java.util.Map;
 
 import com.xeiam.xchart.StyleManager.ChartTheme;
-import com.xeiam.xchart.internal.Histogram;
 import com.xeiam.xchart.internal.chartpart.ChartPainter;
 import com.xeiam.xchart.internal.style.Theme;
 
@@ -222,22 +221,22 @@ public class Chart {
     return chartPainter.getAxisPair().addSeries(seriesName, xDataNumber, yDataNumber, errorBarDataNumber);
   }
 
-  /**
-   * Add a series for a histogram
-   * 
-   * @param seriesName
-   * @param data
-   * @param numBins
-   * @param min
-   * @param max
-   * @return
-   */
-  public Series addSeries(String seriesName, Collection<? extends Number> data, int numBins, double min, double max) {
-
-    Histogram histogram1 = new Histogram(data, numBins, min, max);
-
-    return chartPainter.getAxisPair().addSeries(seriesName, histogram1.getxAxisData(), histogram1.getyAxisData(), null);
-  }
+  // /**
+  // * Add a series for a histogram
+  // *
+  // * @param seriesName
+  // * @param data
+  // * @param numBins
+  // * @param min
+  // * @param max
+  // * @return
+  // */
+  // public Series addSeries(String seriesName, Collection<? extends Number> data, int numBins, double min, double max) {
+  //
+  // Histogram histogram1 = new Histogram(data, numBins, min, max);
+  //
+  // return chartPainter.getAxisPair().addSeries(seriesName, histogram1.getxAxisData(), histogram1.getyAxisData(), null);
+  // }
 
   /**
    * Set the chart title

xchart/src/main/java/com/xeiam/xchart/internal/Histogram.java → xchart/src/main/java/com/xeiam/xchart/Histogram.java

@@ -13,20 +13,23 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package com.xeiam.xchart.internal;
+package com.xeiam.xchart;
 
 import java.util.ArrayList;
 import java.util.Collection;
+import java.util.Collections;
 import java.util.Iterator;
 import java.util.List;
 
 /**
+ * This class can be used to create histogram data for histogram bar charts
+ * 
  * @author timmolter
  */
 public class Histogram {
 
-  private final List<Double> xAxisData; // bin centers
-  private final List<Double> yAxisData; // frequency counts
+  private List<Double> xAxisData; // bin centers
+  private List<Double> yAxisData; // frequency counts
   private final Collection<? extends Number> originalData;
   private final int numBins;
   private final double min;
@@ -34,6 +37,34 @@ public class Histogram {
 
   /**
    * Constructor
+   * 
+   * @param data
+   * @param numBins
+   */
+  public Histogram(Collection<? extends Number> data, int numBins) {
+
+    this.numBins = numBins;
+    this.originalData = data;
+
+    List<Double> dataAsList = new ArrayList<Double>();
+    Iterator<? extends Number> itr = data.iterator();
+    while (itr.hasNext()) {
+      dataAsList.add(((Number) itr.next()).doubleValue());
+    }
+    Collections.sort(dataAsList);
+    this.min = dataAsList.get(0);
+    this.max = dataAsList.get(dataAsList.size() - 1);
+
+    init();
+  }
+
+  /**
+   * Constructor
+   * 
+   * @param data
+   * @param numBins
+   * @param min
+   * @param max
    */
   public Histogram(Collection<? extends Number> data, int numBins, double min, double max) {
 
@@ -45,14 +76,19 @@ public class Histogram {
     // this.min = data[0];
     // this.max = data[data.length - 1];
 
+    init();
+  }
+
+  private void init() {
+
     double[] tempYAxisData = new double[numBins];
     final double binSize = (max - min) / numBins;
 
     // y axis data
-    Iterator<? extends Number> itr = data.iterator();
+    Iterator<? extends Number> itr = originalData.iterator();
     while (itr.hasNext()) {
 
-      int bin = (int) (((Double) itr.next() - min) / binSize); // changed this from numBins
+      int bin = (int) ((((Number) itr.next()).doubleValue() - min) / binSize); // changed this from numBins
       if (bin < 0) { /* this data is smaller than min */
       }
       else if (bin >= numBins) { /* this data point is bigger than max */