Delphi TChart using AddNullXY and trend function

Question

I have TeeChart version 7.07.

I have a chart with a FastLineSeries with 400 datapoints (x is date and y is used%). the first 200 are valid dates with actual measured % values. the next 200 are valid dates in the future with 0 as the YValue that were added using AddNullXY (date,0,datelabel). I also have a FastLineSeries as a trend function with a Datasource of the first series.

The problem is the 0's in the last 200 values are changing the trend line. I want the trend line to extend into the future dates where I can predict the date the disks will fill up. I have tried the IgnoreNulls property but it was no help.

Is this possible? Steve...

Answer 1

Try using NaN instead of 0.