Dundas Chart for ASP.NET
FilterTopN(Int32,Series,Series,String,Boolean) Method
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Dundas.Charting.WebControl Namespace > DataManipulator Class > FilterTopN Method : FilterTopN(Int32,Series,Series,String,Boolean) Method

Visual Basic (Declaration)
Visual Basic (Usage)
C#

pointCount: The number of data points that the filtering operation will not remove (or mark as empty).
Number of top/bottom points to return.

inputSeries: Series object that is filtered.
Input series.

outputSeries: Series object that stores the remaining data points. If it does not exist an exception will be thrown.
Output series.

usingValue: The data point value that is examined (e.g. "X", "Y", "Y2", etc.).
Defines which value of the point use in comparison (X, Y, Y2, ...).

getTopValues: Largest values are kept if true, otherwise smallest values are kept.
Indicate that N top values must be retrieved, otherwise N bottom values.

Enterprise Edition Only Feature. Filters all data points in a series except for a specified number of point's with the smallest or largest values.

Keeps only N top/bottom points of the series.

Syntax

Visual Basic (Declaration)
Public Overloads Sub FilterTopN( _ ByVal pointCount As Integer, _ ByVal inputSeries As Series, _ ByVal outputSeries As Series, _ ByVal usingValue As String, _ ByVal getTopValues As Boolean _ )

Visual Basic (Declaration)

Public Overloads Sub FilterTopN( _
   ByVal pointCount As Integer, _
   ByVal inputSeries As Series, _
   ByVal outputSeries As Series, _
   ByVal usingValue As String, _
   ByVal getTopValues As Boolean _
)

Visual Basic (Usage) Copy Code

Visual Basic (Usage)	Copy Code
`Dim instance As DataManipulator Dim pointCount As Integer Dim inputSeries As Series Dim outputSeries As Series Dim usingValue As String Dim getTopValues As Boolean instance.FilterTopN(pointCount, inputSeries, outputSeries, usingValue, getTopValues)`

Dim instance As DataManipulator
Dim pointCount As Integer
Dim inputSeries As Series
Dim outputSeries As Series
Dim usingValue As String
Dim getTopValues As Boolean
 
instance.FilterTopN(pointCount, inputSeries, outputSeries, usingValue, getTopValues)

C#
public void FilterTopN( int pointCount, Series inputSeries, Series outputSeries, string usingValue, bool getTopValues )

Parameters

pointCount: The number of data points that the filtering operation will not remove (or mark as empty).
Number of top/bottom points to return.
inputSeries: Series object that is filtered.
Input series.
outputSeries: Series object that stores the remaining data points. If it does not exist an exception will be thrown.
Output series.
usingValue: The data point value that is examined (e.g. "X", "Y", "Y2", etc.).
Defines which value of the point use in comparison (X, Y, Y2, ...).
getTopValues: Largest values are kept if true, otherwise smallest values are kept.
Indicate that N top values must be retrieved, otherwise N bottom values.

Example

The following sample code filters Series1, and only 10 data points that have the smallest second Y-values are stored in Series2, which is the only displayed series. We will assume we are dealing with a bubble chart, that uses Y2 for its bubble sizes.

Visual Basic Copy Code

Visual Basic	Copy Code
`Imports Dundas.Charting.WebControl<CRLF> ...<CRLF><CRLF>Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load<CRLF> <CRLF> ' Filter out all points except 10 data points with the smallest Y2 values<CRLF> Chart1.DataManipulator.FilterTopN(10, Chart1.Series("Series1"), Chart1.Series("Series2"), "Y2", False)<CRLF> <CRLF> ' Do not display Series1<CRLF> Chart1.Series("Series1").ChartArea = ""<CRLF> <CRLF>End Sub`

Imports Dundas.Charting.WebControl<CRLF> ...<CRLF><CRLF>Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load<CRLF> <CRLF> ' Filter out all points except 10 data points with the smallest Y2 values<CRLF> Chart1.DataManipulator.FilterTopN(10, Chart1.Series("Series1"), Chart1.Series("Series2"), "Y2", False)<CRLF> <CRLF> ' Do not display Series1<CRLF> Chart1.Series("Series1").ChartArea = ""<CRLF> <CRLF>End Sub

C# Copy Code

C#	Copy Code
`using Dundas.Charting.WebControl;<CRLF> ...<CRLF><CRLF>protected void Page_Load(object sender, System.EventArgs e)<CRLF>{<CRLF><CRLF> // Filter out all points except 10 data points with the smallest Y2 values<CRLF> Chart1.DataManipulator.FilterTopN(10, Chart1.Series["Series1"], Chart1.Series["Series2"], "Y2", false);<CRLF><CRLF> // Do not display Series1<CRLF> Chart1.Series["Series1"].ChartArea = "";<CRLF><CRLF>}`

using Dundas.Charting.WebControl;<CRLF>  ...<CRLF><CRLF>protected void Page_Load(object sender, System.EventArgs e)<CRLF>{<CRLF><CRLF>    // Filter out all points except 10 data points with the smallest Y2 values<CRLF>    Chart1.DataManipulator.FilterTopN(10, Chart1.Series["Series1"], Chart1.Series["Series2"], "Y2", false);<CRLF><CRLF>    // Do not display Series1<CRLF>    Chart1.Series["Series1"].ChartArea = "";<CRLF><CRLF>}

Remarks

This method removes all data points from the input series except for the specified number of points that have the largest or smallest values (depends on the getTopValues parameter).

The data point value that is examined is determined by the usingValue parameter, and the remaining points are stored in the output series.

If the specified output series has not been created and added to the SeriesCollection when this function call is made an exception will be thrown.

Filtered points can be either removed from a series (default) or displayed as empty points, depending on the FilterSetEmptyPoints value.

Requirements

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

Syntax

Parameters

Example

Remarks

Requirements

See Also

Reference