Page 1 of 1

Using Series.AddNullXY

Posted: Thu Jul 01, 2004 5:37 pm
by 9080335
When using the AddNullXY method on a Series, to draw a line, is there some mechanism available to be able to check to see if a specific point in the series was added by the AddNullXY method? I need to be able to display the specific value of trace at a specific X position. When displaying the point that was added by the AddNullXY method, I need to display NULL as the value. Other than using a specific value for the Y value of the data point and checking the points in the series for that specific value, I can see no mechanism available. The issue with using a specific value is that the value is used when determining the max/min axis values when turning on axis autoscaling and may cause issues in autoscaling the axis. Any guidance would be greatly appreciated.

I am using version 6.0.0.4 of the TeeChart Pro Activex v6 control. This is being used within an HTML page.

Thanks,

Scott Small

Posted: Thu Jul 01, 2004 6:39 pm
by Pep
Hi Scott,

for TeeChart "null" point is point with it's ValueColor set to clNone. So, checking each point PointColor should do the trick. BTW, you can also use

TChart.Series(x).IsNull(ValueIndex)

function to determine whether a point is null or not. This method uses the same code (compares PointColor to clNone and returns true if PointColor(ValueIndex) = clNone.