TChartValueList.Locate
TChartValueList
function Locate(Const AValue: TChartValue): Integer; overload;
Unit
TeEngine
Description
This new function returns the corresponding point index which has the specified Value. You can use it to calculate X co-ordinates based on Y values or vice-versa:
tmp:=LineSeries1.XValues.Locate(EncodeDate(2007,1,1));
if tmp<>-1 then ...