added errors bars!

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

@@ -151,8 +151,8 @@ public class Axis implements IChartPart {
   }
 
   /**
-     * 
-     */
+   * @return
+   */
   public int getSizeHint() {
 
     if (direction == Direction.X) { // X-Axis

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

@@ -58,7 +58,7 @@ public class AxisPair implements IChartPart {
    * @param xData
    * @param yData
    */
-  public Series addSeries(String seriesName, Collection<Number> xData, Collection<Number> yData) {
+  public Series addSeries(String seriesName, Collection<Number> xData, Collection<Number> yData, Collection<Number> errorBars) {
 
     // Sanity checks
     if (seriesName == null) {
@@ -82,18 +82,21 @@ public class AxisPair implements IChartPart {
 
     Series series;
     if (xData != null) {
-      series = new Series(seriesName, xData, yData);
+      series = new Series(seriesName, xData, yData, errorBars);
     } else { // generate xData
       Collection<Number> generatedXData = new ArrayList<Number>();
       for (int i = 1; i < yData.size(); i++) {
         generatedXData.add(i);
       }
-      series = new Series(seriesName, generatedXData, yData);
+      series = new Series(seriesName, generatedXData, yData, errorBars);
     }
 
     // Sanity check
     if (xData != null && xData.size() != yData.size()) {
-      throw new IllegalArgumentException("X and Y-Axis lengths are not the same!!! ");
+      throw new IllegalArgumentException("X and Y-Axis sizes are not the same!!! ");
+    }
+    if (errorBars != null && errorBars.size() != yData.size()) {
+      throw new IllegalArgumentException("errorbars and Y-Axis sizes are not the same!!! ");
     }
 
     seriesMap.put(seriesCount++, series);

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

@@ -25,7 +25,6 @@ import java.util.List;
 
 import com.xeiam.xchart.interfaces.IChartPart;
 
-
 /**
  * An axis tick.
  */
@@ -145,8 +144,8 @@ public class AxisTick implements IChartPart {
   }
 
   /**
-     * 
-     */
+   * 
+   */
   private void determineAxisTick() {
 
     // System.out.println("workingSpace= " + workingSpace);

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

@@ -52,6 +52,9 @@ public class Chart {
     height = pHeight;
   }
 
+  /**
+   * @param g
+   */
   public void paint(final Graphics2D g) {
 
     // Sanity check
@@ -121,7 +124,12 @@ public class Chart {
    */
   public Series addSeries(String seriesName, Collection<Number> xData, Collection<Number> yData) {
 
-    return axisPair.addSeries(seriesName, xData, yData);
+    return axisPair.addSeries(seriesName, xData, yData, null);
+  }
+
+  public Series addSeries(String seriesName, Collection<Number> xData, Collection<Number> yData, Collection<Number> errorBars) {
+
+    return axisPair.addSeries(seriesName, xData, yData, errorBars);
   }
 
   /**
@@ -132,6 +140,7 @@ public class Chart {
    * @param yData double[]
    * @return
    */
+  @Deprecated
   public Series addSeries(String seriesName, double[] xData, double[] yData) {
 
     Collection<Number> xDataNumber = null;
@@ -146,7 +155,7 @@ public class Chart {
       yDataNumber.add(new Double(d));
     }
 
-    return axisPair.addSeries(seriesName, xDataNumber, yDataNumber);
+    return axisPair.addSeries(seriesName, xDataNumber, yDataNumber, null);
   }
 
   public void setChartTitle(String title) {

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

@@ -39,6 +39,12 @@ public enum ChartColor {
 
   Color color;
 
+  /**
+   * Get a AWT Color Object
+   * 
+   * @param chartColor
+   * @return
+   */
   protected static Color getAWTColor(ChartColor chartColor) {
 
     return chartColor.color;

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

@@ -20,7 +20,6 @@ import java.awt.Rectangle;
 
 import com.xeiam.xchart.interfaces.IChartPart;
 
-
 /**
  * @author timmolter
  */

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

@@ -23,6 +23,7 @@ import java.util.Map;
 
 import com.xeiam.xchart.interfaces.IChartPart;
 import com.xeiam.xchart.series.Series;
+import com.xeiam.xchart.series.SeriesLineStyle;
 
 /**
  * @author timmolter
@@ -70,17 +71,25 @@ public class PlotContent implements IChartPart {
       Collection<Number> yData = series.getyData();
       double yMin = chart.getAxisPair().getYAxis().getMin();
       double yMax = chart.getAxisPair().getYAxis().getMax();
+      Collection<Number> errorBars = series.getErrorBars();
 
       int previousX = Integer.MIN_VALUE;
       int previousY = Integer.MIN_VALUE;
 
       Iterator<Number> xItr = xData.iterator();
       Iterator<Number> yItr = yData.iterator();
+      Iterator<Number> ebItr = null;
+      if (errorBars != null) {
+        ebItr = errorBars.iterator();
+      }
       while (xItr.hasNext()) {
 
         double x = xItr.next().doubleValue();
         double y = yItr.next().doubleValue();
-
+        double eb = 0.0;
+        if (errorBars != null) {
+          eb = ebItr.next().doubleValue();
+        }
         if (!Double.isNaN(x) && !Double.isNaN(y)) {
 
           int xTransform = (int) (xLeftMargin + ((x - xMin) / (xMax - xMin) * xTickSpace));
@@ -115,6 +124,17 @@ public class PlotContent implements IChartPart {
             g.setColor(series.getMarkerColor());
             series.getMarker().paint(g, xOffset, yOffset);
           }
+
+          // paint errorbar
+          if (errorBars != null) {
+            g.setColor(ChartColor.getAWTColor(ChartColor.DARK_GREY));
+            g.setStroke(SeriesLineStyle.getBasicStroke(SeriesLineStyle.SOLID));
+            int bottom = (int) (-1 * bounds.getHeight() * eb / (yMax - yMin));
+            int top = (int) (bounds.getHeight() * eb / (yMax - yMin));
+            g.drawLine(xOffset, yOffset + bottom, xOffset, yOffset + top);
+            g.drawLine(xOffset - 3, yOffset + bottom, xOffset + 3, yOffset + bottom);
+            g.drawLine(xOffset - 3, yOffset + top, xOffset + 3, yOffset + top);
+          }
         }
       }
     }

src/main/java/com/xeiam/xchart/series/Series.java

@@ -18,6 +18,7 @@ package com.xeiam.xchart.series;
 import java.awt.BasicStroke;
 import java.awt.Color;
 import java.util.Collection;
+import java.util.Iterator;
 
 import com.xeiam.xchart.series.markers.Marker;
 
@@ -32,6 +33,8 @@ public class Series {
 
   protected Collection<Number> yData;
 
+  protected Collection<Number> errorBars;
+
   /** the minimum value of axis range */
   private double xMin;
 
@@ -63,11 +66,12 @@ public class Series {
    * @param xData
    * @param yData
    */
-  public Series(String name, Collection<Number> xData, Collection<Number> yData) {
+  public Series(String name, Collection<Number> xData, Collection<Number> yData, Collection<Number> errorBars) {
 
     this.name = name;
     this.xData = xData;
     this.yData = yData;
+    this.errorBars = errorBars;
 
     // xData
     double[] xMinMax = findMinMax(xData);
@@ -75,7 +79,12 @@ public class Series {
     this.xMax = xMinMax[1];
 
     // yData
-    double[] yMinMax = findMinMax(yData);
+    double[] yMinMax = null;
+    if (errorBars == null) {
+      yMinMax = findMinMax(yData);
+    } else {
+      yMinMax = findMinMaxWithErrorBars(yData, errorBars);
+    }
     this.yMin = yMinMax[0];
     this.yMax = yMinMax[1];
     // System.out.println(yMin);
@@ -116,6 +125,37 @@ public class Series {
     return new double[] { min, max };
   }
 
+  /**
+   * Finds the min and max of a dataset accounting for error bars
+   * 
+   * @param data
+   * @return
+   */
+  private double[] findMinMaxWithErrorBars(Collection<Number> data, Collection<Number> errorBars) {
+
+    Double min = null;
+    Double max = null;
+
+    Iterator<Number> itr = data.iterator();
+    Iterator<Number> ebItr = errorBars.iterator();
+    while (itr.hasNext()) {
+      double number = itr.next().doubleValue();
+      double eb = ebItr.next().doubleValue();
+      verify(number);
+      if (min == null || (number - eb) < min) {
+        if (!Double.isNaN(number)) {
+          min = number - eb;
+        }
+      }
+      if (max == null || (number + eb) > max) {
+        if (!Double.isNaN(number)) {
+          max = number + eb;
+        }
+      }
+    }
+    return new double[] { min, max };
+  }
+
   /**
    * Checks for invalid values in data array
    * 
@@ -145,6 +185,11 @@ public class Series {
     return yData;
   }
 
+  public Collection<Number> getErrorBars() {
+
+    return errorBars;
+  }
+
   public double getxMin() {
 
     return xMin;

src/main/java/com/xeiam/xchart/series/SeriesLineStyle.java

@@ -41,9 +41,23 @@ public enum SeriesLineStyle {
   DOT_DOT(3, new BasicStroke(1, BasicStroke.CAP_BUTT, BasicStroke.JOIN_BEVEL, 10.0f, new float[] { 1.0f, 1.0f }, 0.0f));
 
   int id;
+
   BasicStroke basicStroke;
+
   private static int nextId = 0;
 
+  /**
+   * Constructor
+   * 
+   * @param id
+   * @param color
+   */
+  private SeriesLineStyle(int id, BasicStroke basicStroke) {
+
+    this.id = id;
+    this.basicStroke = basicStroke;
+  }
+
   private static final Map<Integer, SeriesLineStyle> idLookup = new HashMap<Integer, SeriesLineStyle>();
   static {
     for (SeriesLineStyle seriesLineStyle : EnumSet.allOf(SeriesLineStyle.class)) {
@@ -61,11 +75,22 @@ public enum SeriesLineStyle {
     nextId = 0;
   }
 
-  protected static BasicStroke getBasicStroke(SeriesLineStyle seriesMarker) {
+  /**
+   * Get an AWT Stroke
+   * 
+   * @param seriesMarker
+   * @return
+   */
+  public static BasicStroke getBasicStroke(SeriesLineStyle seriesMarker) {
 
     return seriesMarker.basicStroke;
   }
 
+  /**
+   * Gets the next Stroke
+   * 
+   * @return
+   */
   protected static BasicStroke getNextBasicStroke() {
 
     SeriesLineStyle seriesLineStyle = idLookup.get(nextId);
@@ -76,15 +101,4 @@ public enum SeriesLineStyle {
     return idLookup.get(nextId++).basicStroke;
   }
 
-  /**
-   * Constructor
-   * 
-   * @param id
-   * @param color
-   */
-  private SeriesLineStyle(int id, BasicStroke basicStroke) {
-
-    this.id = id;
-    this.basicStroke = basicStroke;
-  }
 }

src/test/java/com/xeiam/xchart/example/Example8.java

+/**
+ * Copyright 2011-2012 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.example;
+
+import java.util.ArrayList;
+import java.util.Collection;
+
+import com.xeiam.xchart.Chart;
+import com.xeiam.xchart.series.Series;
+import com.xeiam.xchart.series.SeriesColor;
+import com.xeiam.xchart.series.SeriesLineStyle;
+import com.xeiam.xchart.series.SeriesMarker;
+import com.xeiam.xchart.swing.SwingWrapper;
+
+/**
+ * Create a Chart with error bars
+ * 
+ * @author timmolter
+ */
+public class Example8 {
+
+  public static void main(String[] args) {
+
+    // generates data
+    int size = 10;
+    Collection<Number> xData1 = new ArrayList<Number>();
+    Collection<Number> yData1 = new ArrayList<Number>();
+    Collection<Number> errorBars = new ArrayList<Number>();
+    for (int i = 0; i <= size; i++) {
+      xData1.add(i);
+      yData1.add(10 * Math.exp(-i));
+      errorBars.add(Math.random() + .3);
+    }
+
+    // Create Chart
+    Chart chart = new Chart(440, 300);
+
+    // Customize Chart
+    chart.setChartTitleVisible(false);
+    chart.setChartLegendVisible(false);
+    chart.setAxisTitlesVisible(false);
+
+    // Series 1
+    Series series1 = chart.addSeries("10^(-x)", xData1, yData1, errorBars);
+    series1.setLineColor(SeriesColor.PURPLE);
+    series1.setLineStyle(SeriesLineStyle.DASH_DASH);
+    series1.setMarkerColor(SeriesColor.GREEN);
+    series1.setMarker(SeriesMarker.SQUARE);
+
+    new SwingWrapper(chart).displayChart();
+  }
+
+}