Dynamic Charts......

ramki · Post by **ramki** » Tue Jun 26, 2007 7:57 am

Hi to All......
Plese Can any one help me to get Dynamic Chart using JFreeChart,i mean what are the concepts we have to use...is there anyway to get dynamic one...............

Thanks in Advance......

Ramki....

jwenting · Post by **jwenting** » Thu Jun 28, 2007 1:45 pm

define "dynamic chart" first of all.

ramki · Post by **ramki** » Fri Jun 29, 2007 6:22 am

HI jwenting....
Here Dynamic Chart means...when we update our Database anytime...it has to fetch on screen as a chart,i am using JFree Chart,but how to get this result.
I hope u got what i am trying to say....

Thanks..

harrisppr · Post by **harrisppr** » Fri Jun 29, 2007 9:21 am

There is an applet example in the developer guide. It plots real-time-like curves. I think it is similar to your dynamic chart concept.

Actually, I am doing similar thing. I have developed an applet that can plot living timeseriers that I randomly generated on the client side. I am trying to let the applet to request to the web server, which in order requests to my database. I am using PHP script on the web server at the moment. The php script has heard the GET request from the applet, but the applet fails to hear the response from the web server. I am one step away from success.

Anybody can help me please? Any help will be deeply appreciated.

jwenting · Post by **jwenting** » Fri Jun 29, 2007 12:32 pm

Well, if you have some code that monitors that database and detects the updates happening it can also fire off something that regenerates the chart.

Problem is that with stockmarket data if your instruments are highly volatile those updates may well come closer together than the time required to create a new chart, so you're better off triggering that using some other mechanism.
As humans aren't really capable of handling extremely fast moving information, it doesn't matter if your updates are closer than 10 seconds together for example (and probably a minute or even longer would be acceptable).
If you present it faster they'll likely be unable to interpret the information before the screen changes again.

ramki · Post by **ramki** » Mon Jul 02, 2007 9:43 am

Hi jwenting...
Thanks for reply......
i got what ur trying to say.... I am using Applets to generate realtime charts and i am able to get real time chart for every 10 seconds refresh(for every 10 sec.it will conncet to DB and gets the updated value)....but,if u have large amount of data in DB(in GB's) and u trying to connect DB for every 10 secs, the performance will be slow...right....
here i structup....please can u help me regarding this issue....

Thanks in Advnace......

jwenting · Post by **jwenting** » Tue Jul 03, 2007 2:34 pm

well, if you can't get the chart generated fast enough you've hit a performance bottleneck.
Identify it, and fix it. How to fix it you'll have to figure out yourself as it completely depends on your specific situation.