Steema Central

Code: Select all

		Screen->Cursor = crHourGlass;
	  int num_leads = ECG->getNumLeads() ;
	  int freq= ECG->getFreq();
	  long M= ECG->getNumSamp();
	  long K = M/num_leads;
	  ScrollBar2->Min = 0;
	  ScrollBar2->Max = floor(1.0*K/(UpDown1->Position*freq));
	  size_t num = freq * UpDown1->Position; // windows size
	  size_t start = ScrollBar2->Position*num; // Page number
	  double Dt = 1.0/freq;
	  double t =0.0;
	  char ld_name[64];
	  for (int j  = 0; j < num_leads; j++) { // plot lead by lead
			ECGPlot[j] = new TFastLineSeries(Chart1);
			ECGPlot[j]->ParentChart = Chart1;
			t=start*Dt;
			double *data = new double[num];
			int read =ECG->getData(j,start,num,data);
			// data table for lead j
			for (int i = 0; i < read ; i++)
			{
				t+=Dt;
				ECGPlot[j]->AddXY(t,data[i]);
			}
			delete [] data;
			sprintf(ld_name, "Lead-%s", ECG->LeadText(j));
			ECGPlot[j]->Title=ld_name;
		}
		Chart1->BottomAxis->SetMinMax(start*Dt, start*Dt+num*Dt);
		Chart1->BottomAxis->Increment=1.0;
		Chart1->CustomAxes->Clear();
	   int n = Chart1->SeriesCount();
	   int D = 100/n;
	   for (int i = 0; i < n; i++) {
		   TChartAxis *Ax = new TChartAxis(Chart1->CustomAxes);
		   Ax->Axis->Color = Chart1->Series[i]->Color;
		   Ax->StartPosition = i*D;
		   Ax->EndPosition = Min(i*D +D-2,100);
		   Ax->PositionPercent = 0;
		   Ax->LabelStyle =talNone;
		   Chart1->Series[i]->CustomVertAxis = Ax;
		   Chart1->Series[i]->Color= clNavy;
	   }

Code: Select all

uses series;

procedure TForm1.FormCreate(Sender: TObject);
var i, j, nSeries, nPoints: Integer;
    XValues: array of Single;
    YValues: array of array of Single;
begin
  Chart1.View3D:=false;

  nSeries:=20;
  nPoints:=100000;

  SetLength(XValues,nPoints);
  SetLength(YValues,nSeries);
  for i:=0 to nSeries-1 do
  begin
    SetLength(YValues[i],nPoints);
    YValues[i][0]:=random*100+1000;
  end;
  XValues[0]:=0;
  for j:=Low(XValues)+1 to High(XValues) do
  begin
    XValues[j]:=j*5;
    for i:=Low(YValues) to High(YValues) do
      YValues[i][j]:=YValues[i][j-1] + random*10-5;
  end;


  //option 1: AddXY
  //35 Mb with 20 series and 100.000 pts per series
  //19 Mb with the same data and TEEVALUESINGLE and arrays of singles instead of arrays of doubles
{  for i:=0 to nSeries-1 do
  begin
    Chart1.AddSeries(TLineSeries.Create(self));
    Chart1[i].BeginUpdate;
    for j:=0 to nPoints-1 do
      Chart1[i].AddXY(XValues[j],YValues[i][j]);
    Chart1[i].EndUpdate;
  end;}


  //option 2: Assign Arrays
  //19 Mb with 20 series and 100.000 pts per series
  //11 Mb with the same data and TEEVALUESINGLE and arrays of singles instead of arrays of doubles
  for i:=0 to nSeries-1 do
  begin
    Chart1.AddSeries(TLineSeries.Create(self));
    With Chart1[i].XValues do
    begin
      Value:=TChartValues(XValues);
      Count:=Length(XValues);
      Modified:=True;
    end;
    With Chart1[i].YValues do
    begin
      Value:=TChartValues(YValues[i]);
      Count:=Length(YValues[i]);
      Modified:=True;
    end;
  end;

  Chart1.Axes.Left.Automatic:=true;
end;