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El · Guest

I would like to create charts in real time like the one shown on the
performance tab of Windows Task Manager.
I would be feeding it things like transaction per second numbers every
second and it would chart it as a line chart.

Thanks.

Horst Reichert · Guest

If you are not fixed on using TChart you might have a look at:
http://www.rt-science.com/toolsexample.html

It is just as assigning values to an array.

Regards Horst

Narcís Calvet · Guest

Hello,

At the URL below you'll find an article on how to create real-time charts
with TeeChart and optimize its performance.

http://www.teechart.net/reference/modules.php?name=News&file=article&sid=6

--
Best Regards,

Narcis Calvet
Steema Support Central
http://support.steema.com

"Important note: If you are a TeeChart registered customer, please post your
support questions at Steema's Support monitored Forums for customers:
http://support.steema.com for a prompter reply."

El wrote:

David Berneda · Guest

Hi El
If your data comes every second then you don't need lots of speed,
so you can use simple code like the one below to setup a chart, a line series,
and then at every second delete one point at the beggining of the line and
add a new point at the end to simulate automatic scroll like Task Manager does.

Download this example here:
http://www.steema.com/support/teechart/7/tutorials/simple_realtime/TeeChart_Simple_RealTime.zip

regards
david
www.teechart.com

uses
Chart, Series, ExtCtrls;

Const
MaxPoints = 20;

var
Chart1 : TChart;
Line1 : TLineSeries;
Timer1 : TTimer;

procedure TForm1.FormCreate(Sender: TObject);
begin
// Create the Chart
Chart1:=TChart.Create(Self);
Chart1.Parent:=Self;
Chart1.Align:=alClient;

// Create the Line
Line1:=TLineSeries.Create(Self);
Chart1.AddSeries(Line1);

// Add some random data
Line1.GetHorizAxis.SetMinMax(0,MaxPoints-1);
Line1.FillSampleValues(MaxPoints);

// Cosmetic changes
Chart1.Color:=clBlack;
Line1.Color:=clLime;
Line1.GetHorizAxis.LabelsFont.Color:=clWhite;
Line1.GetHorizAxis.Grid.Color:=clGreen;
Line1.GetVertAxis.LabelsFont.Color:=clWhite;
Line1.GetVertAxis.Grid.Color:=clGreen;
Chart1.Walls.Left.Color:=clSilver;

// Add a one-second Timer
Timer1:=TTimer.Create(Self);
Timer1.Interval:=1000;
Timer1.OnTimer:=Timer1Timer;
end;

procedure TForm1.Timer1Timer(Sender: TObject);
begin
// Remove first point
if Line1.Count>=MaxPoints then Line1.Delete(0);

// Add new point
Line1.Add(Line1.YValues.Last+Random(50)-25);

// Reset "X" to start at zero
Line1.XValues.FillSequence;
end;

"El" <elias.berelian (AT) snet (DOT) net> wrote in message news:45804132$1 (AT) newsgroups (DOT) borland.com...

El · Guest

Thanks David.
That helped a lot. I am not using Delphi, so I had to convert to C. Some
TChart methods I coul not find equivalents of.
For example:
Line1.GetHorizAxis.SetMinMax(0,MaxPoints-1);
Line1.YValues.Last
// Reset "X" to start at zero
Line1.XValues.FillSequence;

Thanks again,
Elias
"David Berneda" <david (AT) steema (DOT) com> wrote in message
news:4581373e (AT) newsgroups (DOT) borland.com...

David Berneda · Guest

Hi Elias
I've ported the example to C++, using TeeChart Standard v4 (the free one included with C++ Builder)
instead of latest TeeChart Pro v8.
See code below. Works fine in my machine.

If you need more help try also posting your questions at our public newsgroups:
news://www.steema.net

regards
david
www.teechart.com

#include "Unit1.h"
#include <Chart.hpp>
#include <Series.hpp>
#include <ExtCtrls.hpp>

//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;

const
MaxPoints = 20;

TChart *Chart1;
TLineSeries *Line1;
TTimer *Timer1;

//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
: TForm(Owner)
{
// Create the Chart
Chart1=new TChart(this);
Chart1->Parent=this;
Chart1->Align=alClient;

// Create the Line
Line1=new TLineSeries(this);
Line1->ParentChart=Chart1;

// Add some random data
Line1->GetHorizAxis->SetMinMax(0,MaxPoints-1);
Line1->FillSampleValues(MaxPoints);

// Cosmetic changes
Chart1->Color=clBlack;
Line1->SeriesColor=clLime;
Line1->GetHorizAxis->LabelsFont->Color=clWhite;
Line1->GetHorizAxis->Grid->Color=clGreen;
Line1->GetVertAxis->LabelsFont->Color=clWhite;
Line1->GetVertAxis->Grid->Color=clGreen;
Chart1->LeftWall->Brush->Color=clSilver;

// Add a one-second Timer
Timer1=new TTimer(this);
Timer1->Interval=1000;
Timer1->OnTimer=Timer1Timer;

}
//---------------------------------------------------------------------------

void __fastcall TForm1::Timer1Timer(TObject *Sender)
{
// Remove first point
if (Line1->Count() >= MaxPoints)
{
Line1->Delete(0);
}

// Add new point
Line1->Add(Line1->YValues->Last()+random(50)-25);

// Reset "X" to start at zero
Line1->XValues->FillSequence();

}
//---------------------------------------------------------------------------

"El" <elias.berelian (AT) snet (DOT) net> wrote in message news:45817ce8$1 (AT) newsgroups (DOT) borland.com...

El · Guest

Thanks again David. Works fine.

Regards, Elias

"David Berneda" <david (AT) steema (DOT) com> wrote in message
news:4581ab1f$1 (AT) newsgroups (DOT) borland.com...