カスタム サマリーの作成

Public Class StandardDeviationCalc
Inherits SynchronousSummaryCalculator
Public Overrides ReadOnly Property SummaryExecution As SummaryExecution
   Get
      Return Infragistics.SummaryExecution.PriorToFilteringAndPaging
   End Get
End Property
Public Overrides Function Summarize(ByVal data As IQueryable, ByVal fieldKey As String) As Object
   Dim convertedData As IQueryable = CType(data,IQueryable)
   ' 中間計算に使用される変数
   Dim sum As Double = 0
   Dim count As Integer = 0
   Dim squaredsum As Double = 0
   Dim tempVal As Double = 0
   For Each item As NorthwindServiceReference.Product In convertedData
      ' UnitsInStock 列の値
      tempVal = Convert.ToDouble(item.UnitsInStock)
      count = (count + 1)
      ' UnitsInStock 列の合計値
      sum = (sum + tempVal)
      ' UnitsInStock 列の二乗値
      squaredsum = (squaredsum _
      + (tempVal * tempVal))
    Next
     If ((count < 2) _
     OrElse (sum = 0)) Then
     Return 0
   End If
   ' UnitsInStock 列の平均を計算します
   Dim theAverage As Double = (sum / count)
   ' StandardDeviation 式
   Dim theDeviation As Double = ((squaredsum _
    - (sum * theAverage)) _
   / (count - 1))
   ' UnitsInStock 列の標準偏差を返します
   Return Math.Sqrt(theDeviation)
  End Function
End Class

public class StandardDeviationCalc : SynchronousSummaryCalculator
{
   public override SummaryExecution? SummaryExecution
   {
      get
      {
         return Infragistics.SummaryExecution.PriorToFilteringAndPaging;
      }
   }
   public override object Summarize(IQueryable data, string fieldKey)
   {
       IQueryable<NorthwindServiceReference.Product> convertedData = (IQueryable<NorthwindServiceReference.Product>)data;
       // 中間計算に使用される変数
       double sum = 0;
       int count = 0;
       double squaredsum = 0;
       double tempVal = 0;
       foreach (NorthwindServiceReference.Product item in convertedData)
       {
          // UnitsInStock 列の値
          tempVal = Convert.ToDouble(item.UnitsInStock);
          count++;
          // UnitsInStock 列の合計値
          sum += tempVal;
          // UnitsInStock 列の二乗値
          squaredsum += tempVal * tempVal;
       }
       if (count < 2 || sum == 0)
          return 0;
       // UnitsInStock 列の平均を計算します
       double theAverage = sum / count;
       // StandardDeviation 式
       double theDeviation = (squaredsum - sum * theAverage) / (count - 1);
       // UnitsInStock 列の標準偏差を返します
       return Math.Sqrt(theDeviation);
    }
 }

Public Class StandardDeviationOperand
   Inherits SummaryOperandBase
   Private myCalc As StandardDeviationCalc
   Protected Overrides ReadOnly Property DefaultRowDisplayLabel As String
      Get
         Return "Standard Deviation"
      End Get
   End Property
   Protected Overrides ReadOnly Property DefaultSelectionDisplayLabel As String
      Get
         Return "Standard Deviation"
       End Get
   End Property
   Public Overrides ReadOnly Property SummaryCalculator As SummaryCalculatorBase
      Get
         If (myCalc Is Nothing) Then
            Me.myCalc = New StandardDeviationCalc
         End If
       Return Me.myCalc
     End Get
   End Property
End Class

public class StandardDeviationOperand : SummaryOperandBase
{
   StandardDeviationCalc myCalc;
   protected override string DefaultRowDisplayLabel
   {
      get { return "Standard Deviation"; }
   }
   protected override string DefaultSelectionDisplayLabel
   {
      get { return "Standard Deviation"; }
   }
   public override SummaryCalculatorBase SummaryCalculator
   {
      get
      {
         if (myCalc == null)
         {
            this.myCalc = new StandardDeviationCalc();
         }
         return this.myCalc;
         }
      }
   }
}

Me.MyDataGrid.Columns.DataColumns("UnitsInStock").SummaryColumnSettings.SummaryOperands.Add(New StandardDeviationOperand)

// 集計オペランドを UnitsInStock 列に追加します
 this.MyDataGrid.Columns.DataColumns["UnitsInStock"].SummaryColumnSettings.SummaryOperands.Add(new StandardDeviationOperand());