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TeeChart - want to scroll, not scale

Hi,

  I would like to use TeeChart to emulate a history tape; much like that of
an EKG. So my question is how do I get TeeChart to scroll to the right to
keep up with the current point in a line series instead of scaling the whole
graph to fit the entire contents. In the demo, a point is added to the
series and the first point (0) is deleted to achieve this effect. I would
like to have the whole history of points and be able to scroll back to see
them.

Is this possible?

Thanks!

- Jody Dawkins

 

Re:TeeChart - want to scroll, not scale


Hi Jody,

Quote
>   I would like to use TeeChart to emulate a history tape; much like that of
> an EKG. So my question is how do I get TeeChart to scroll to the right to
> keep up with the current point in a line series instead of scaling the whole
> graph to fit the entire contents. In the demo, a point is added to the
> series and the first point (0) is deleted to achieve this effect. I would
> like to have the whole history of points and be able to scroll back to see
> them.

> Is this possible?

it is with TPlot:

http://Chemware.hypermart.net/

cheers,

Mat

ps:version 2 will be uploaded in the the next or two,
________________________________________

rm -rf /mnt/windows/
________________________________________

Dr Mat Ballard,
CSIRO Molecular Science,
Bag 10,
Clayton South MDC,
Vic 3169. AUSTRALIA.
tel: 61-3-9545-2425
fax: 61-3-9545-2415
mat.ball...@molsci.csiro.au
URL: http://www.wark.csiro.au/ballard/
Linux Registered User #6854

Re:TeeChart - want to scroll, not scale


Hi, Jody.

Yes, this is possible. For TeeChart scrolling/zooming operations are merely
changing axis scale. In your case you only need to change bottom
(horizontal) axis scale. This will give you the scroll effect. Something
like this:

{ show only last 10 days }
With Chart1.BottomAxis do
begin
  Automatic := true;
  AutomaticMinimum := false;
  Minimum := Maximum - 10.0; { show last 10 days - example }
end;

Then you can use sligtly different code to scroll to specific position:

{ show only last 10 days }
With Chart1.BottomAxis do
begin
  Automatic := false;
  SetMinMax(startpos,startpos+0.5); { show 12 hrs of data, starting at
startpos}
end;
--
Regards,

Marjan Slatinek
TeeChart Support
mar...@steema.com
-------------------------------------

Quote
"Jody Dawkins" <j...@shift4.com> wrote in message news:3af9757d$2_2@dnews...
> Hi,

>   I would like to use TeeChart to emulate a history tape; much like that
of
> an EKG. So my question is how do I get TeeChart to scroll to the right to
> keep up with the current point in a line series instead of scaling the
whole
> graph to fit the entire contents. In the demo, a point is added to the
> series and the first point (0) is deleted to achieve this effect. I would
> like to have the whole history of points and be able to scroll back to see
> them.

> Is this possible?

> Thanks!

> - Jody Dawkins

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