lazarus/components/tachart/demo/chartsource/frmderivative.pas

102 lines
2.4 KiB
ObjectPascal

unit frmDerivative;
{$mode ObjFPC}{$H+}
interface
uses
SysUtils, Classes, Math,
Forms, Controls, StdCtrls, ExtCtrls, Spin,
TAGraph, TASeries, TASources;
type
TDerivativeFrame = class(TFrame)
cbAccDirDerivative: TComboBox;
cbSmooth: TCheckBox;
ccsDerivative: TCalculatedChartSource;
chDerivative: TChart;
chDerivativeLineDeriv: TLineSeries;
chDerivativeLineOrig: TLineSeries;
lblAccumulationRange: TLabel;
lcsDerivative: TListChartSource;
ParamsPanel: TPanel;
rgDataShape: TRadioGroup;
seAccumulationRange: TSpinEdit;
procedure cbAccDirDerivativeChange(Sender: TObject);
procedure cbSmoothChange(Sender: TObject);
procedure rgDataShapeClick(Sender: TObject);
procedure seAccumulationRangeChange(Sender: TObject);
private
procedure CreateDataForDerivative;
public
constructor Create(AOwner: TComponent); override;
end;
implementation
{$R *.lfm}
constructor TDerivativeFrame.Create(AOwner: TComponent);
begin
inherited;
CreateDataForDerivative;
end;
procedure TDerivativeFrame.cbAccDirDerivativeChange(Sender: TObject);
begin
ccsDerivative.AccumulationDirection := TChartAccumulationDirection(cbAccDirDerivative.ItemIndex);
end;
procedure TDerivativeFrame.cbSmoothChange(Sender: TObject);
begin
if cbSmooth.Checked then
ccsDerivative.AccumulationMethod := camSmoothDerivative
else
ccsDerivative.AccumulationMethod := camDerivative;
end;
procedure TDerivativeFrame.CreateDataForDerivative;
const
N = 100;
MIN_X = -10;
MAX_X = 10;
EPS = 1e-6;
var
i: Integer;
x, y: Double;
begin
lcsDerivative.Clear;
if rgDataShape.ItemIndex = 6 then
for i := 0 to 9 do
lcsDerivative.Add(i - IfThen(i > 6, 1, 0), i)
else
for i := 0 to N - 1 do begin
x := MIN_X + (MAX_X - MIN_X) / (N - 1) * i;
if SameValue(x, 0.0, EPS) then x := 0;
case rgDataShape.ItemIndex of
0: y := x;
1: y := Sin(x);
2: if x = 0 then y := 1 else y := Sin(x) / x;
3: y := Exp(-x / 3);
4: y := Exp(-Sqr((x - 2.5) / 2.5));
5: y := Exp(-Sqr((x - 2.5) / 2.5)) + 0.05 * (Random - 0.5);
end;
lcsDerivative.Add(x, y);
end;
end;
procedure TDerivativeFrame.rgDataShapeClick(Sender: TObject);
begin
CreateDataForDerivative;
end;
procedure TDerivativeFrame.seAccumulationRangeChange(Sender: TObject);
begin
ccsDerivative.AccumulationRange := seAccumulationRange.Value;
end;
end.