DataView.IsInstance

Prototypes

static boolean IsInstance( DataView view )

Return Value

If view is an object of the DataView-derived class from which the method IsInstance was called, the return value is true. Otherwise, the return value is false.

Parameters

DataView view
An object of a DataView-derived class.

Remarks

Use this method to determine whether an object is an instance of a particular DataView-derived class. The class from which this method is called determines how the method responds. If you call Histogram.IsInstance for a Histogram object, the method returns true. If you call Plot2D.IsInstance for a Histogram object, the method returns true. However, if you call ScatterPlot.IsInstance for a Histogram object, the method returns false.

Example

x = normal( j(100,1,12345) );

declare Histogram plot1;

plot1 = Histogram.Create( "Histogram", x );

plot1.ShowDensity();

plot1.AppendActionMenuItem( "Overlay Normal Curve",

    "run OverlayNormalCurve();" );

declare BoxPlot plot2;

plot2 = BoxPlot.Create( "BoxPlot", x );

plot2.AppendActionMenuItem( "Overlay Normal Curve",

    "run OverlayNormalCurve();" );

start OverlayNormalCurve();

    /* create data for standard normal curve */

    x = T( do(-3,3,0.1) );

    twoPI = 8*atan(1);

    y = exp( -x#x/2 ) / sqrt( twoPI );

    declare Plot2D plot;

    plot = DataView.GetInitiator();

    /* add curve depnding on plot class */

    if Histogram.IsInstance(plot) then do;

        plot.DrawUseDataCoordinates();

        plot.DrawLine( x, y );

        end;

    else if BoxPlot.IsInstance(plot) then do;

        plot.GetAxisViewRange( YAXIS, ymin, ymax );

        plot.DrawUseNormalizedCoordinates( 0, 3, ymin, ymax );

        plot.DrawLine( y, x );

        end;

finish;