Interface IChartTrendLine

Represents ChartTrendLine interface.

Namespace: Syncfusion.XlsIO

Assembly: Syncfusion.XlsIO.NET.dll

Syntax

public interface IChartTrendLine

Properties

Backward

Represents number of periods that the trend line extends backward.

Declaration

double Backward { get; set; }

Property Value

Type
System.Double

Examples

The following code illustrates how to set backward forecast value for IChartTrendLine object.

        using (ExcelEngine excelEngine = new ExcelEngine())
        {
            //Create worksheet
            IApplication application = excelEngine.Excel;
            application.DefaultVersion = ExcelVersion.Excel2013;
            IWorkbook workbook = application.Workbooks.Create(1);
            IWorksheet sheet = workbook.Worksheets[0];

            //Add data
            sheet.Range["A1"].Value2 = -1;
            sheet.Range["B1"].Value2 = 0;
            sheet.Range["C1"].Value2 = 1;
            sheet.Range["A2"].Value2 = 10;
            sheet.Range["B2"].Value2 = 20;
            sheet.Range["C2"].Value2 = 30;

            //Create chart
            IChart chart = sheet.Charts.Add();

            //Add serie
            IChartSerie serie = chart.Series.Add();

            //Set serie Y Values
            serie.Values = sheet.Range["A2:C2"];

            //Set serie X Values
            serie.CategoryLabels = sheet.Range["A1:C1"];

            //Set chart type
            chart.ChartType = ExcelChartType.Scatter_Markers;

            //Set X axis minimum and maximum values
            chart.PrimaryCategoryAxis.MinimumValue = -2;
            chart.PrimaryCategoryAxis.MaximumValue = 2;

            //Get chart trendlines collection
            IChartTrendLines trendLines = serie.TrendLines;

            //Add trendline
            IChartTrendLine trendline = trendLines.Add();

            //Set backward forecast value
            trendline.Backward = 3;

            //Save and Dispose
            workbook.SaveAs("Chart.xlsx");
            workbook.Close();            
        }

Border

Represents border object. Read-only.

Declaration

IChartBorder Border { get; }

Property Value

Type
IChartBorder

Examples

The following code illustrates how to access and format the IChartBorder for IChartTrendLine

        using (ExcelEngine excelEngine = new ExcelEngine())
        {
            //Create worksheet
            IApplication application = excelEngine.Excel;
            application.DefaultVersion = ExcelVersion.Excel2013;
            IWorkbook workbook = application.Workbooks.Create(1);
            IWorksheet sheet = workbook.Worksheets[0];

            //Add data
            sheet.Range["A1"].Text = "Jan";
            sheet.Range["B1"].Text = "Feb";
            sheet.Range["C1"].Text = "Mar";
            sheet.Range["A2"].Value2 = 10;
            sheet.Range["B2"].Value2 = 20;
            sheet.Range["C2"].Value2 = 30;

            //Create chart
            IChart chart = sheet.Charts.Add();

            //Add serie
            IChartSerie serie = chart.Series.Add();

            //Set serie Y Values
            serie.Values = sheet.Range["A2:C2"];

            //Set serie X Values
            serie.CategoryLabels = sheet.Range["A1:C1"];

            //Set chart type
            chart.ChartType = ExcelChartType.Column_Clustered;                     

            //Get chart trendlines collection
            IChartTrendLines trendLines = serie.TrendLines;

            //Add trendline
            IChartTrendLine trendline = trendLines.Add();

            //Set trendline broder properties
            trendline.Border.ColorIndex = ExcelKnownColors.Red;

            //Save and Dispose
            workbook.SaveAs("Chart.xlsx");
            workbook.Close();            
        }

Chart3DOptions

Gets the IThreeDFormat object. Read-only.[Deprecated]

Declaration

IThreeDFormat Chart3DOptions { get; }

Property Value

Type
IThreeDFormat

DataLabel

Returns data label. Read-only.

Declaration

IChartTextArea DataLabel { get; }

Property Value

Type
IChartTextArea

Remarks

To get DataLabel DisplayRSquared or DisplayEquation must be set to true. Otherwise exception will be thrown.

Examples

The following code illustrates how to enable and set IChartTextArea text for IChartTrendLine object.

       using (ExcelEngine excelEngine = new ExcelEngine())
       {
           //Create worksheet
           IApplication application = excelEngine.Excel;
           application.DefaultVersion = ExcelVersion.Excel2013;
           IWorkbook workbook = application.Workbooks.Create(1);
           IWorksheet sheet = workbook.Worksheets[0];

           //Add data
           sheet.Range["A1"].Text = "Jan";
           sheet.Range["B1"].Text = "Feb";
           sheet.Range["C1"].Text = "Mar";
           sheet.Range["A2"].Value = "10";
           sheet.Range["B2"].Value = "20";
           sheet.Range["C2"].Value = "30";
           sheet.Range["A3"].Value = "15";
           sheet.Range["B3"].Value = "25";
           sheet.Range["C3"].Value = "35";

           //Create chart
           IChart chart = sheet.Charts.Add();

           //Set range
           chart.DataRange = sheet.Range["A1:C3"];

           //Set chart type
           chart.ChartType = ExcelChartType.Column_Clustered;

           //Get chart serie
           IChartSerie serie = chart.Series[0];

           //Get chart trendlines collection
           IChartTrendLines trendLines = serie.TrendLines;

           //Add trendline
           IChartTrendLine trendline = trendLines.Add();

           //Enable trendline data label by DisplayRSquared         
           trendline.DisplayRSquared = true;

           //Set data label text 
           trendline.DataLabel.Text = "y=10*x";

           //Get trendline data label Text
           Console.WriteLine(trendline.DataLabel.Text);

           //Save and Dispose
           workbook.SaveAs("Chart.xls");
           workbook.Close();
           Console.ReadKey();
       }
//Output will be
// y=10*x

DisplayEquation

True if the equation for the trend line is displayed on the chart.

Declaration

bool DisplayEquation { get; set; }

Property Value

Type
System.Boolean

Examples

The following code illustrates how to display equation for IChartTrendLine object.

        using (ExcelEngine excelEngine = new ExcelEngine())
        {
            //Create worksheet
            IApplication application = excelEngine.Excel;
            application.DefaultVersion = ExcelVersion.Excel2013;
            IWorkbook workbook = application.Workbooks.Create(1);
            IWorksheet sheet = workbook.Worksheets[0];

            //Add data
            sheet.Range["A1"].Text = "Jan";
            sheet.Range["B1"].Text = "Feb";
            sheet.Range["C1"].Text = "Mar";
            sheet.Range["A2"].Value = "10";
            sheet.Range["B2"].Value = "20";
            sheet.Range["C2"].Value = "30";
            sheet.Range["A3"].Value = "15";
            sheet.Range["B3"].Value = "25";
            sheet.Range["C3"].Value = "35";

            //Create chart
            IChart chart = sheet.Charts.Add();

            //Set range
            chart.DataRange = sheet.Range["A1:C3"];

            //Set chart type
            chart.ChartType = ExcelChartType.Column_Clustered;

            //Get chart serie
            IChartSerie serie = chart.Series[0];

            //Get chart trendlines collection
            IChartTrendLines trendLines = serie.TrendLines;

            //Add trendline
            IChartTrendLine trendline = trendLines.Add();

            //Set equation in trendline
            trendline.DisplayEquation = true;

            //Save and Dispose
            workbook.SaveAs("Chart.xlsx");
            workbook.Close();            
        }

DisplayRSquared

True if the R-squared value of the trend line is displayed on the chart.

Declaration

bool DisplayRSquared { get; set; }

Property Value

Type
System.Boolean

Examples

The following code illustrates how to display RSquared value for IChartTrendLine object.

        using (ExcelEngine excelEngine = new ExcelEngine())
        {
            //Create worksheet
            IApplication application = excelEngine.Excel;
            application.DefaultVersion = ExcelVersion.Excel2013;
            IWorkbook workbook = application.Workbooks.Create(1);
            IWorksheet sheet = workbook.Worksheets[0];

            //Add data
            sheet.Range["A1"].Text = "Jan";
            sheet.Range["B1"].Text = "Feb";
            sheet.Range["C1"].Text = "Mar";
            sheet.Range["A2"].Value = "10";
            sheet.Range["B2"].Value = "20";
            sheet.Range["C2"].Value = "30";
            sheet.Range["A3"].Value = "15";
            sheet.Range["B3"].Value = "25";
            sheet.Range["C3"].Value = "35";

            //Create chart
            IChart chart = sheet.Charts.Add();

            //Set range
            chart.DataRange = sheet.Range["A1:C3"];

            //Set chart type
            chart.ChartType = ExcelChartType.Column_Clustered;

            //Get chart serie
            IChartSerie serie = chart.Series[0];

            //Get chart trendlines collection
            IChartTrendLines trendLines = serie.TrendLines;

            //Add trendline
            IChartTrendLine trendline = trendLines.Add();

            //Set RSquared value for trendline
            trendline.DisplayRSquared = true;

            //Save and Dispose
            workbook.SaveAs("Chart.xlsx");
            workbook.Close();            
        }

Forward

Represents number of periods that the trend line extends forward.

Declaration

double Forward { get; set; }

Property Value

Type
System.Double

Examples

The following code illustrates how to set Forward forecast value for IChartTrendLine object.

        using (ExcelEngine excelEngine = new ExcelEngine())
        {
            //Create worksheet
            IApplication application = excelEngine.Excel;
            application.DefaultVersion = ExcelVersion.Excel2013;
            IWorkbook workbook = application.Workbooks.Create(1);
            IWorksheet sheet = workbook.Worksheets[0];

            //Add data
            sheet.Range["A1"].Value2 = -1;
            sheet.Range["B1"].Value2 = 0;
            sheet.Range["C1"].Value2 = 1;
            sheet.Range["A2"].Value2 = 10;
            sheet.Range["B2"].Value2 = 20;
            sheet.Range["C2"].Value2 = 30;

            //Create chart
            IChart chart = sheet.Charts.Add();

            //Add serie
            IChartSerie serie = chart.Series.Add();

            //Set serie Y Values
            serie.Values = sheet.Range["A2:C2"];

            //Set serie X Values
            serie.CategoryLabels = sheet.Range["A1:C1"];

            //Set chart type
            chart.ChartType = ExcelChartType.Scatter_Markers;

            //Set X axis minimum and maximum values
            chart.PrimaryCategoryAxis.MinimumValue = -2;
            chart.PrimaryCategoryAxis.MaximumValue = 2;

            //Get chart trendlines collection
            IChartTrendLines trendLines = serie.TrendLines;

            //Add trendline
            IChartTrendLine trendline = trendLines.Add();

            //Set forward forecast value
            trendline.Forward = 3;

            //Save and Dispose
            workbook.SaveAs("Chart.xlsx");
            workbook.Close();            
        }

Intercept

Represents point where the trend line crosses the value axis.

Declaration

double Intercept { get; set; }

Property Value

Type
System.Double

Examples

The following code illustrates how to set intercept value for IChartTrendLine object.

        using (ExcelEngine excelEngine = new ExcelEngine())
        {
            //Create worksheet
            IApplication application = excelEngine.Excel;
            application.DefaultVersion = ExcelVersion.Excel2013;
            IWorkbook workbook = application.Workbooks.Create(1);
            IWorksheet sheet = workbook.Worksheets[0];

            //Add data
            sheet.Range["A1"].Value2 = 1;
            sheet.Range["B1"].Value2 = 2;
            sheet.Range["C1"].Value2 = 3;
            sheet.Range["A2"].Value2 = 10;
            sheet.Range["B2"].Value2 = 20;
            sheet.Range["C2"].Value2 = 30;

            //Create chart
            IChart chart = sheet.Charts.Add();

            //Add serie
            IChartSerie serie = chart.Series.Add();

            //Set serie Y Values
            serie.Values = sheet.Range["A2:C2"];

            //Set serie X Values
            serie.CategoryLabels = sheet.Range["A1:C1"];

            //Set chart type
            chart.ChartType = ExcelChartType.Scatter_Markers;                     

            //Get chart trendlines collection
            IChartTrendLines trendLines = serie.TrendLines;

            //Add trendline
            IChartTrendLine trendline = trendLines.Add();

            //Set intercept value
            trendline.Intercept = 10;    

            //Save and Dispose
            workbook.SaveAs("Chart.xlsx");
            workbook.Close();
        }

InterceptIsAuto

True if the point where the trend line crosses the value axis is automatically determined by the regression.

Declaration

bool InterceptIsAuto { get; set; }

Property Value

Type
System.Boolean

Examples

The following code illustrates how to check whether the IChartTrendLine object intercept value is automatic or not.

        using (ExcelEngine excelEngine = new ExcelEngine())
        {
            //Create worksheet
            IApplication application = excelEngine.Excel;
            application.DefaultVersion = ExcelVersion.Excel2013;
            IWorkbook workbook = application.Workbooks.Create(1);
            IWorksheet sheet = workbook.Worksheets[0];

            //Add data
            sheet.Range["A1"].Value2 = 1;
            sheet.Range["B1"].Value2 = 2;
            sheet.Range["C1"].Value2 = 3;
            sheet.Range["A2"].Value2 = 10;
            sheet.Range["B2"].Value2 = 20;
            sheet.Range["C2"].Value2 = 30;

            //Create chart
            IChart chart = sheet.Charts.Add();

            //Add serie
            IChartSerie serie = chart.Series.Add();

            //Set serie Y Values
            serie.Values = sheet.Range["A2:C2"];

            //Set serie X Values
            serie.CategoryLabels = sheet.Range["A1:C1"];

            //Set chart type
            chart.ChartType = ExcelChartType.Scatter_Markers;                     

            //Get chart trendlines collection
            IChartTrendLines trendLines = serie.TrendLines;

            //Add trendline
            IChartTrendLine trendline = trendLines.Add();

            //Set intercept value
            trendline.Intercept = 10;

            //Check trendline intercept is automatic
            Console.WriteLine("Is Trendline Intercept value is automatic:" + trendline.InterceptIsAuto.ToString());

            //Save and Dispose
            workbook.SaveAs("Chart.xlsx");
            workbook.Close();
            Console.ReadKey();
        }
// Output will be
// Is Trendline Intercept value is automatic:False

Name

Gets or Sets the name of trend line.

Declaration

string Name { get; set; }

Property Value

Type
System.String

Examples

The following code illustrates how to access name from IChartTrendLine object.

        using (ExcelEngine excelEngine = new ExcelEngine())
        {
            //Create worksheet
            IApplication application = excelEngine.Excel;
            application.DefaultVersion = ExcelVersion.Excel2013;
            IWorkbook workbook = application.Workbooks.Create(1);
            IWorksheet sheet = workbook.Worksheets[0];

            //Add data
            sheet.Range["A1"].Text = "Jan";
            sheet.Range["B1"].Text = "Feb";
            sheet.Range["C1"].Text = "Mar";
            sheet.Range["A2"].Value = "10";
            sheet.Range["B2"].Value = "20";
            sheet.Range["C2"].Value = "30";
            sheet.Range["A3"].Value = "15";
            sheet.Range["B3"].Value = "25";
            sheet.Range["C3"].Value = "35";

            //Create chart
            IChart chart = sheet.Charts.Add();

            //Set range
            chart.DataRange = sheet.Range["A1:C3"];

            //Set chart type
            chart.ChartType = ExcelChartType.Column_Clustered;

            //Get chart serie
            IChartSerie serie = chart.Series[0];

            //Get chart serie trendlines collection
            IChartTrendLines trendLines = serie.TrendLines;

            //Add trendline
            IChartTrendLine trendline = trendLines.Add(ExcelTrendLineType.Logarithmic);                       

            //Get trendline Name
            Console.WriteLine(trendline.Name);

            //Save and Dispose
            workbook.SaveAs("Chart.xlsx");
            workbook.Close();
            Console.ReadKey();
        }
//Output will be
// Log. (Serie3)

NameIsAuto

Represents whether the trendline name is default or not.

Declaration

bool NameIsAuto { get; set; }

Property Value

Type
System.Boolean

Examples

The following code illustrates how to check whether the IChartTrendLine object name is default or not.

        using (ExcelEngine excelEngine = new ExcelEngine())
        {
            //Create worksheet
            IApplication application = excelEngine.Excel;
            application.DefaultVersion = ExcelVersion.Excel2013;
            IWorkbook workbook = application.Workbooks.Create(1);
            IWorksheet sheet = workbook.Worksheets[0];

            //Add data
            sheet.Range["A1"].Text = "Jan";
            sheet.Range["B1"].Text = "Feb";
            sheet.Range["C1"].Text = "Mar";
            sheet.Range["A2"].Value = "10";
            sheet.Range["B2"].Value = "20";
            sheet.Range["C2"].Value = "30";
            sheet.Range["A3"].Value = "15";
            sheet.Range["B3"].Value = "25";
            sheet.Range["C3"].Value = "35";

            //Create chart
            IChart chart = sheet.Charts.Add();

            //Set range
            chart.DataRange = sheet.Range["A1:C3"];

            //Set chart type
            chart.ChartType = ExcelChartType.Column_Clustered;

            //Get chart serie
            IChartSerie serie = chart.Series[0];

            //Get chart serie trendlines collection
            IChartTrendLines trendLines = serie.TrendLines;

            //Add trendline
            IChartTrendLine trendline = trendLines.Add(ExcelTrendLineType.Logarithmic);                       

            //Set trendline name
            trendline.Name = "Trendline 1";

            //Check trendline name is automatic
            Console.WriteLine(trendline.NameIsAuto);

            //Save and Dispose
            workbook.SaveAs("Chart.xlsx");
            workbook.Close();
            Console.ReadKey();
        }
//Output will be
// False

Order

Represents for Moving Average and Polynomial trend line type order value.

Declaration

int Order { get; set; }

Property Value

Type
System.Int32

Examples

The following code illustrates how to set order value for IChartTrendLine object.

        using (ExcelEngine excelEngine = new ExcelEngine())
        {
            //Create worksheet
            IApplication application = excelEngine.Excel;
            application.DefaultVersion = ExcelVersion.Excel2013;
            IWorkbook workbook = application.Workbooks.Create(1);
            IWorksheet sheet = workbook.Worksheets[0];

            //Add data
            sheet.Range["A1"].Text = "Jan";
            sheet.Range["B1"].Text = "Feb";
            sheet.Range["C1"].Text = "Mar";
            sheet.Range["A2"].Value2 = 10;
            sheet.Range["B2"].Value2 = 20;
            sheet.Range["C2"].Value2 = 30;

            //Create chart
            IChart chart = sheet.Charts.Add();

            //Add serie
            IChartSerie serie = chart.Series.Add();

            //Set serie Y Values
            serie.Values = sheet.Range["A2:C2"];

            //Set serie X Values
            serie.CategoryLabels = sheet.Range["A1:C1"];

            //Set chart type
            chart.ChartType = ExcelChartType.Column_Clustered;                     

            //Get chart trendlines collection
            IChartTrendLines trendLines = serie.TrendLines;

            //Add trendline
            IChartTrendLine trendline = trendLines.Add();

            //Set trendline type
            trendline.Type = ExcelTrendLineType.Polynomial;

            //Set trendline order
            trendline.Order = 6;

            //Save and Dispose
            workbook.SaveAs("Chart.xlsx");
            workbook.Close();            
        }

Shadow

Gets the shadow.Read-only.

Declaration

IShadow Shadow { get; }

Property Value

Type
IShadow

Examples

The following code illustrates how to access and format the IShadow for IChartTrendLine

         using (ExcelEngine excelEngine = new ExcelEngine())
         {
             //Create worksheet
             IApplication application = excelEngine.Excel;
             application.DefaultVersion = ExcelVersion.Excel2013;
             IWorkbook workbook = application.Workbooks.Create(1);
             IWorksheet sheet = workbook.Worksheets[0];

             //Add data
             sheet.Range["A1"].Text = "Jan";
             sheet.Range["B1"].Text = "Feb";
             sheet.Range["C1"].Text = "Mar";
             sheet.Range["A2"].Value2 = 10;
             sheet.Range["B2"].Value2 = 20;
             sheet.Range["C2"].Value2 = 30;

             //Create chart
             IChart chart = sheet.Charts.Add();

             //Add serie
             IChartSerie serie = chart.Series.Add();

             //Set serie Y Values
             serie.Values = sheet.Range["A2:C2"];

             //Set serie X Values
             serie.CategoryLabels = sheet.Range["A1:C1"];

             //Set chart type
             chart.ChartType = ExcelChartType.Column_Clustered;                     

             //Get chart trendlines collection
             IChartTrendLines trendLines = serie.TrendLines;

             //Add trendline
             IChartTrendLine trendline = trendLines.Add();

             //Set trendline shadow color
             trendline.Shadow.ShadowColor = System.Drawing.Color.Red;

             //Set trendline shadow outer presets
             trendline.Shadow.ShadowOuterPresets = Excel2007ChartPresetsOuter.OffsetDiagonalTopRight;

             //Save and Dispose
             workbook.SaveAs("Chart.xlsx");
             workbook.Close();            
         }

Type

Gets or Sets trend line type.

Declaration

ExcelTrendLineType Type { get; set; }

Property Value

Type
ExcelTrendLineType

Examples

The following code illustrates how to set ExcelTrendLineType for IChartTrendLine object.

        using (ExcelEngine excelEngine = new ExcelEngine())
        {
            //Create worksheet
            IApplication application = excelEngine.Excel;
            application.DefaultVersion = ExcelVersion.Excel2013;
            IWorkbook workbook = application.Workbooks.Create(1);
            IWorksheet sheet = workbook.Worksheets[0];

            //Add data
            sheet.Range["A1"].Text = "Jan";
            sheet.Range["B1"].Text = "Feb";
            sheet.Range["C1"].Text = "Mar";
            sheet.Range["A2"].Value = "10";
            sheet.Range["B2"].Value = "20";
            sheet.Range["C2"].Value = "30";
            sheet.Range["A3"].Value = "15";
            sheet.Range["B3"].Value = "25";
            sheet.Range["C3"].Value = "35";

            //Create chart
            IChart chart = sheet.Charts.Add();

            //Set range
            chart.DataRange = sheet.Range["A1:C3"];

            //Set chart type
            chart.ChartType = ExcelChartType.Column_Clustered;

            //Get chart serie
            IChartSerie serie = chart.Series[0];

            //Get chart serie trendlines collection
            IChartTrendLines trendLines = serie.TrendLines;

            //Add trendline
            IChartTrendLine trendline = trendLines.Add();                       

            //Set trendline type
            trendline.Type = ExcelTrendLineType.Polynomial;          

            //Save and Dispose
            workbook.SaveAs("Chart.xlsx");
            workbook.Close();
        }

Methods

ClearFormats()

Clears current trend line formats.

Declaration

void ClearFormats()

Examples

The following code illustrates how to clear the formats of IChartTrendLine object.

        using (ExcelEngine excelEngine = new ExcelEngine())
        {
            //Create worksheet
            IApplication application = excelEngine.Excel;
            application.DefaultVersion = ExcelVersion.Excel2013;
            IWorkbook workbook = application.Workbooks.Create(1);
            IWorksheet sheet = workbook.Worksheets[0];

            //Add data
            sheet.Range["A1"].Text = "Jan";
            sheet.Range["B1"].Text = "Feb";
            sheet.Range["C1"].Text = "Mar";
            sheet.Range["A2"].Value = "10";
            sheet.Range["B2"].Value = "20";
            sheet.Range["C2"].Value = "30";
            sheet.Range["A3"].Value = "15";
            sheet.Range["B3"].Value = "25";
            sheet.Range["C3"].Value = "35";

            //Create chart
            IChart chart = sheet.Charts.Add();

            //Set range
            chart.DataRange = sheet.Range["A1:C3"];

            //Set chart type
            chart.ChartType = ExcelChartType.Column_Clustered;

            //Get chart serie
            IChartSerie serie = chart.Series[0];

            //Get chart trendlines collection
            IChartTrendLines trendLines = serie.TrendLines;

            //Add trendline
            IChartTrendLine trendline = trendLines.Add();

            //Set RSquared value for trendline
            trendline.DisplayRSquared = true;

            //Set trendline border color
            trendline.Border.ColorIndex = ExcelKnownColors.Red;

            //Set trendline name
            trendline.Name = "trendline 1";

            //Check trendline before clearing the formats
            Console.WriteLine("Before clearing the formats\n------");
            Console.WriteLine("Is default line color applied in trendline:" + trendline.Border.IsAutoLineColor);
            Console.WriteLine("Trendline name:" + trendline.Name);
            Console.WriteLine("Is R-squared value displayed:" + trendline.DisplayRSquared);

            //Clear the trendline formats
            trendline.ClearFormats();

            //Check trendline after clearing the formats
            Console.WriteLine("After clearing the formats\n------");
            Console.WriteLine("Is default line color applied in trendline:" + trendline.Border.IsAutoLineColor);
            Console.WriteLine("Trendline name:" + trendline.Name);
            Console.WriteLine("Is R-squared value displayed:" + trendline.DisplayRSquared);

            //Save and Dispose
            workbook.SaveAs("Chart.xlsx");
            workbook.Close();
            Console.ReadKey();
        }
// Output will be
// Before clearing the formats
//------
//Is default line color applied in trendline:False
//Trendline name:trendline 1
//Is R-squared value displayed:True
//After clearing the formats
//------
//Is default line color applied in trendline:True
//Trendline name:Linear (Serie3)
//Is R-squared value displayed:False