Fix off-by-one calculation of element sum (raster stats).

mmassing · mmassing · commit 2843a939e2e2 · 2010-08-12T08:43:26.000Z
git-svn-id: http://svn.osgeo.org/qgis/trunk@14069 c8812cc2-4d05-0410-92ff-de0c093fc19c
diff --git a/src/core/raster/qgsrasterlayer.cpp b/src/core/raster/qgsrasterlayer.cpp
@@ -824,14 +824,15 @@ const QgsRasterBandStats QgsRasterLayer::bandStatistics( int theBandNo )
             continue; // NULL
           }
 
+          myRasterBandStats.sum += myValue;          
+          ++myRasterBandStats.elementCount;
           //only use this element if we have a non null element
           if ( myFirstIterationFlag )
           {
             //this is the first iteration so initialise vars
             myFirstIterationFlag = false;
             myRasterBandStats.minimumValue = myValue;
             myRasterBandStats.maximumValue = myValue;
-            ++myRasterBandStats.elementCount;
           }               //end of true part for first iteration check
           else
           {
@@ -844,9 +845,6 @@ const QgsRasterBandStats QgsRasterLayer::bandStatistics( int theBandNo )
             {
               myRasterBandStats.maximumValue = myValue;
             }
-
-            myRasterBandStats.sum += myValue;
-            ++myRasterBandStats.elementCount;
           }               //end of false part for first iteration check
         }
       }

Original file line number	Diff line number	Diff line change
`@@ -824,14 +824,15 @@ const QgsRasterBandStats QgsRasterLayer::bandStatistics( int theBandNo )`
`824`	`824`	`continue; // NULL`
`825`	`825`	`}`
`826`	`826`
	`827`	`+ myRasterBandStats.sum += myValue;`
	`828`	`+ ++myRasterBandStats.elementCount;`
`827`	`829`	`//only use this element if we have a non null element`
`828`	`830`	`if ( myFirstIterationFlag )`
`829`	`831`	`{`
`830`	`832`	`//this is the first iteration so initialise vars`
`831`	`833`	`myFirstIterationFlag = false;`
`832`	`834`	`myRasterBandStats.minimumValue = myValue;`
`833`	`835`	`myRasterBandStats.maximumValue = myValue;`
`834`		`- ++myRasterBandStats.elementCount;`
`835`	`836`	`} //end of true part for first iteration check`
`836`	`837`	`else`
`837`	`838`	`{`
`@@ -844,9 +845,6 @@ const QgsRasterBandStats QgsRasterLayer::bandStatistics( int theBandNo )`
`844`	`845`	`{`
`845`	`846`	`myRasterBandStats.maximumValue = myValue;`
`846`	`847`	`}`
`847`		`-`
`848`		`- myRasterBandStats.sum += myValue;`
`849`		`- ++myRasterBandStats.elementCount;`
`850`	`848`	`} //end of false part for first iteration check`
`851`	`849`	`}`
`852`	`850`	`}`