Public Overloads Sub Group( _
   ByVal formula As String, _
   ByVal interval As Double, _
   ByVal intervalType As IntervalType, _
   ByVal inputSeriesName As String, _
   ByVal outputSeriesName As String _
) 

Visual Basic (Usage)	Copy Code
Dim instance As DataManipulator Dim formula As String Dim interval As Double Dim intervalType As IntervalType Dim inputSeriesName As String Dim outputSeriesName As String   instance.Group(formula, interval, intervalType, inputSeriesName, outputSeriesName)

public void Group( 
   string formula,
   double interval,
   IntervalType intervalType,
   string inputSeriesName,
   string outputSeriesName
)

Parameters

formula

The formula(s) to be used for calculating the "grouped" data point values. Multiple formulas can be specified by using comma-separated values.
Grouping formula.

interval

Determines the grouping intervals.
Interval size.

intervalType

Determines the unit of measurement for the grouping intervals.
Interval type.

inputSeriesName

The name(s) of series  that will be grouped.
Comma separated input data series names.

outputSeriesName

The name(s) of series that will store the grouped data points. If a series does not exist it will be created, and an existing series will be cleared before storing grouped points. Must be the same number of series as inputSeriesName or an exception will be thrown .
Comma separated output data series names.

This method divides a series' data points into intervals and replaces the points in each interval with a new data point. The applied formula(s) determine the x and Y-values of these new points.

The interval and intervalType parameters determine the intervals. For example, let's assume that there are numerous data points that are plotted at random for an entire year. To group those points together on a monthly basis the interval would be one (1) and the intervalType would be "IntervalType.Month". To group them by yearly quarters the interval would be three (3) and the intervalType would be "IntervalType.Month".

The first formula is the default, and is applied to all Y-values that are not calculated using subsequent formulas. Formulas specified after the default formula must have a "value" prefix to identify which value they should be applied to. For example, an expression of "SUM, Y2:AVE, X:CENTER" means that an average of secondary Y-values will be calculated, a sum of all other Y-values will be calculated and the resulting data points will be plotted in the middle of their intervals. See Table1  for a listing of possible formulas and their descriptions.

Formulas for X-values merely determine where resulting data points will be plotted for the specified interval (e.g. along the left or right boundary of an interval or in the center of the interval). By default a formula of "FIRST" will be used for X-values (data point is plotted at the left of the interval).

If a specified output series has not been created and added to the SeriesCollection when this function call is made it will be created and added to the collection automatically, and have default series properties (e.g. column chart type, etc.). In addition, the ChartArea property of the series is set to "Default", and if a chart area with the name "Default" exists in the ChartAreasCollection it will be used to draw the chart. If there is no chart area with this name the first ChartArea object in the collection will be used to display the series.

All data points in the given series are grouped (i.e. it is not possible to group only some of a series' data points).

Empty data points will be ignored or treated as zeros, depending on the IgnoreEmptyPoints property (by default IgnoreEmptyPoints is True).

Table 1: Formulas.

Target Platforms: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family, Windows Vista, Windows Server 2008 family

Reference