fixed CSV export of polar data in data mining

java/com.sap.sailing.gwt.ui/src/main/java/com/sap/sailing/gwt/home/desktop/places/whatsnew/resources/SailingAnalyticsNotes.html

@@ -5,6 +5,10 @@
 <div id="mainContent">
     <h4 class="articleHeadline">What's New - SAP Sailing Analytics</h4>
       <div class="innerContent">
+         <h5 class="articleSubheadline">January 2025</h5>
+         <ul class="bulletList">
+            <li>Export of Polar data as CSV has been fixed now in Data Mining.</li>
+         </ul>
          <h5 class="articleSubheadline">December 2024</h5>
          <ul class="bulletList">
             <li>Polar data in Data Mining can now be filtered and grouped by sailor profiles.</li>

java/com.sap.sse.datamining.ui/src/main/java/com/sap/sse/datamining/ui/client/ChartToCsvExporter.java

@@ -46,13 +46,19 @@ public class ChartToCsvExporter {
                 final List<String> columnNames = new ArrayList<>();
                 // collect column names across all series; some may not have points for all columns
                 for (final Series series : chartToExport.getSeries()) {
+                    int minX = Integer.MAX_VALUE;
+                    for (final Point p : series.getPoints()) {
+                        if (p.getX().intValue() < minX) {
+                            minX = p.getX().intValue();
+                        }
+                    }
                     for (Point point : series.getPoints()) {
                         final String pointName = point.getName();
                         final String columnName = pointName != null && !pointName.isEmpty() ? pointName : point.getX().toString();
-                        while (columnNames.size() <= point.getX().intValue()) {
+                        while (columnNames.size() <= point.getX().intValue()-minX) {
                             columnNames.add(columnNames.size(), null);
                         }
-                        columnNames.set(point.getX().intValue(), columnName);
+                        columnNames.set(point.getX().intValue()-minX, columnName);
                     }
                 }
                 for (final String columnName : columnNames) {