paweld/lazarus
1
0
Fork 0
mirror of https://gitlab.com/freepascal.org/lazarus/lazarus.git synced 2025-09-05 11:40:18 +02:00
Code Issues Packages Projects Releases Wiki Activity

TAChart: Skip leftmost point and points with dx = 0 in derivative source

Browse Source 
git-svn-id: trunk@32324 -
This commit is contained in:
ask 2011-09-13 17:43:34 +00:00
parent 6f963be4f2
commit 04b8a56aa0
1 changed files with 10 additions and 11 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

21
components/tachart/tasources.pas
View File

@ -913,20 +913,19 @@ var
prevItem: PChartDataItem;
i, j, ar: Integer;
dx: Double;
t: TChartDataItem;
begin
if AIndex = 0 then begin
AIndex := 1;
ExtractItem(t, AIndex);
FHistory.AddLast(t);
dx := t.X - FHistory.GetPLast(1)^.X;
end
else
dx := FItem.X - FHistory.GetPLast(1)^.X;
FItem.ClearY;
if dx = 0 then exit;
if AIndex = 0 then begin
FItem.X := SafeNan;
exit;
end;
dx := FItem.X - FHistory.GetPLast(1)^.X;
if dx = 0 then begin
FItem.X := SafeNan;
exit;
end;
ar := IfThen(AccumulationRange = 0, MaxInt, AccumulationRange);
ar := math.MinValue([ar, Integer(AIndex + 1), High(COEFFS)]);
ar := MinValue([ar, Integer(AIndex + 1), High(COEFFS)]);
for j := 0 to ar - 1 do begin
prevItem := FHistory.GetPLast(j);
FItem.Y += prevItem^.Y * COEFFS[ar, j];