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CDTrendLayerMBS class

Super class: CDLayerMBS

Type Topic Plugin Version macOS Windows Linux Console & Web iOS
class ChartDirector MBS ChartDirector Plugin 8.2 Yes Yes Yes Yes No
Function: The TrendLayer class represents trend layers.
Notes:
The trend layer performs linear regression analysis on the data points, and represents the result as a best fit straight line with optional confidence and prediction bands.

In linear regression analysis, the data points are assumed to be related by:

y = m * x + c + err
where m and c are constants, and err is a random variable.

Linear regression analysis estimates m, c and err based on available data using the least square method. Using estimated values of m and c, the line y = m * x + c are plotted as the best fit straight line based on available data.

However, as m and c are estimations based on available data, it may not be exactly equal to the "real" m and c. In ChartDirector, the uncertainties are represented visually as a confidence band around the regression line. For example, the 95% confidence band means there are 95% probability that the "real" line is in that band.

To predict a data point (infer y given x), we can use the formula:

y = m * x + c + err
based on estimated values of m, c and err.

The uncertainties of the data point is contributed by the uncertainties in m and c, as well as err. In ChartDirector, the uncertainties of the data points are represented visually as a prediction band around the regression line. For example, a 95% prediction band means there are 95% probability that a data point will be in that band.

The prediction band is always wider than the confidence band. It is because the uncertainties of the regression line is contributed by m and c, while the uncertainties of the data points are contributed by m, c and err. The err term makes the data points less certain that the regression line.
Subclass of the CDLayerMBS class.
This is a subclass of an abstract class. You can't create an instance, but you can get one from various plugin functions.

Feedback, Comments & Corrections

  • 12 methods
    • method addConfidenceBand(confidence as Double, upperFillColor as color, upperEdgeColor as color, upperLineWidth as Integer, lowerFillColor as color, lowerEdgeColor as color, lowerLineWidth as Integer = -1)
    • method addConfidenceBand(confidence as Double, upperFillColor as Integer, upperEdgeColor as Integer = &hFF000000, upperLineWidth as Integer = -1, lowerFillColor as Integer = -1, lowerEdgeColor as Integer = -1, lowerLineWidth as Integer = -1)
    • method addPredictionBand(confidence as Double, upperFillColor as color, upperEdgeColor as color, upperLineWidth as Integer, lowerFillColor as color, lowerEdgeColor as color, lowerLineWidth as Integer = -1)
    • method addPredictionBand(confidence as Double, upperFillColor as Integer, upperEdgeColor as Integer = &hFF000000, upperLineWidth as Integer = -1, lowerFillColor as Integer = -1, lowerEdgeColor as Integer = -1, lowerLineWidth as Integer = -1)
    • method getCoefficient(index as Integer) as Double
    • method getCorrelation as Double
    • method getIntercept as Double
    • method getLine as CDLineObjMBS
    • method getSlope as Double
    • method getStdError as Double
    • method setImageMapWidth(w as Integer)
    • method setRegressionType(regressionType as Integer)

Super class CDLayerMBS

This class has no sub classes.

Some methods using this class:

  • CDXYChartMBS.addTrendLayer(Data() as Double, colorvalue as color, name as string = "", depth as Integer = 0) as CDTrendLayerMBS
  • CDXYChartMBS.addTrendLayer(Data() as Double, colorvalue as Integer = -1, name as string = "", depth as Integer = 0) as CDTrendLayerMBS
  • CDXYChartMBS.addTrendLayer(dates() as date, colorvalue as color, name as string = "", depth as Integer = 0) as CDTrendLayerMBS
  • CDXYChartMBS.addTrendLayer(dates() as date, colorvalue as Integer = -1, name as string = "", depth as Integer = 0) as CDTrendLayerMBS
  • CDXYChartMBS.addTrendLayer(dates() as date, yData() as Double, colorvalue as color, name as string = "", depth as Integer = 0) as CDTrendLayerMBS
  • CDXYChartMBS.addTrendLayer(dates() as date, yData() as Double, colorvalue as Integer = -1, name as string = "", depth as Integer = 0) as CDTrendLayerMBS
  • CDXYChartMBS.addTrendLayer(xData() as Double, yData() as Double, colorvalue as color, name as string = "", depth as Integer = 0) as CDTrendLayerMBS
  • CDXYChartMBS.addTrendLayer(xData() as Double, yData() as Double, colorvalue as Integer = -1, name as string = "", depth as Integer = 0) as CDTrendLayerMBS

Some examples which use this class:


The items on this page are in the following plugins: MBS ChartDirector Plugin.


CDThreeDScatterGroupMBS   -   CDTTFTextMBS





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