Chart Problem

[blue silver]

Dear Fellows,

I have the following problem:

I have a chart with Y-axis the amplitude , and X-axis the time. I am plotting amplitudes for 2 million seconds ! The problem here is: when plotting is over, eventhough I have a scroll back tab , I can only scroll the last few thousand values , but I want to be able to scroll all over the graph ( 0 to 2.000.000) and reach the beginning value time= 0 ! 

Any Idea ? or Solution?

p.s: When I set autoscale of X-axis from properties of the chart , It tries to put all the values within the graph which I don`t want .

I want it to show the last few hundred values of X-axis  , the rest I want to be able to scroll up to beginning time (0)

Thanks Alot !
Regards
silver

[GerdW]

Hi silver,

most probably the history for the chart is set to 2000 values!

Two options:
1) Increase the history length (right-click on chart!)
2) make your own buffer and show only parts of the big array. It doesn't make (a lot of) sense to plot 2 million pixels in chart only ~400 pixels wide...

some cross-linking to this one...


Message Edited by GerdW on 11-27-2007 10:57 AM

[PelleS]

Hi Silver,

You need to set the history length to a number big enough to remember all the samples. Rightclick on chart >> Chart History Length. Then you can set a number up to 2,147,483,647.

If you now deselect autoscale and choose an appropriate scale you can scroll as you wish.

Hope it helps you

[blue silver]

Hello,

thnx for the solution suggestions.It worked that way.
My last question is:

in the chart I see after running the test, I have the " graph palette " for zooming to specific parts. But after I use graph palette , I cant return the original picture again. So now I want to put a button on the GUI  and when you press it you see the original image again.

any idea ?

Best Regards
silver

[PelleS]

Hi again,

You can set the scale programmatically by the property nodes max and minimum. I attach an example.

[GerdW]

Hi silver,

you can also do a "one time autoscale" using the propety nodes to get the full view back!

[blue silver]

would you please convert your code to LV 7.1 ?

thnx

[blue silver]

I use LV 7.1

Message Edited by blue silver on 11-29-2007 12:39 AM

[PelleS]

Here you go.