Working with dynamic scales in waveform graph -> display problem

[sparti]

Hello

I want to use the same waveform graph in the frontpanel for different measurements. These measurements contains 1 to 8 curves, some of them I need to autoscale and others I want to use fixed scales. I wrote a method containing these functions and the functional behaviour is how I expected. But when it runs several times, LabView cannot correctly manage the graph display. Some scales are behind the graph or two scales are at the same position.

Perhaps you have a look at my example VI (LV 7.1), I generate a random Waveform and want to display a random number of curves and some of them in fixed, and some in autorange. The more I run the VI, the more the waveform graph display gets wrong. Does anybody know a solution?

Thank you very much for answering!

sparti.

[xseadog]

Hi

well i ran you Vi:  it functions as you designed. The visible scales indicates how many scales you should see, the value is correct on each run.
Regarding your wiring  practise , ensure that all wires are visible and not hiden behind case selectors.

Normal practise is usually to have one action occur on a case statement, ie don't do anything is false flag set .

if you dewire your case selector in the loop (frame 2) and set value to true then you scales do not jump around or disappear.

My impression is that you are attempting to create every possibility  in the one vi -- why not create several ??

Regards

The wandering xseadog

[sparti]

Hi xseadog

thank you for anwering. First of all, this is only an example VI to demonstrate the behaviour of my application. That is why the code isn't that "perfect". I cannot send the original code because I work in OO by using additional tools which you don't have.

Well the point is that I want to disable some of the scales. After running the VI eg 20 times, the position of the scales changed.

Why I want to do this? I want to display different testtypes in the same waveform viewer. Using the same control makes the code and the handling with this waveform viewer simpler.

[xseadog]

Hi Sparti,

it is not necessary to send the orginal code. If the channel data was saved as a text file then that could be used.
Do you mean that after 20 cycles you wish to disable  some of the graph scales?
Is this for a real time process or post data process?

With regard to disabling scale  I suspect that it could be a problem if you wish to keep the same area format.
 It may be necessary to have some predefined graph templates which you select depending on how
many scales you want visible.

That my 25 ore's worth.

The wandering xseadog

[sparti]

xseadog


The process is not realtime. The graph gets maybee all 20 seconds an update (and the measurements we do are around 10 us).

But each update can contain a different number of channels - therefore the number of scales changes from time to time. And sooner or later (eg after hours) the graph display and its scales get mixed up. In my example VI it gets mixed up quicklier because scale properties change each time.

In my opinion LV does something wrong with those property nodes. Maybee you are right and I need to create different graphs. One single graph would be more flexible and standardize for me that is why I posted this question in this forum.

[xseadog]

Hi Sparti,

by using a template you could  pre analysis you data to select the appropiate display !

xseadog

[Ben]

From the description this sounds like what I thought was a bug, but it was not!

Please review this thread

http://forums.ni.com/ni/board/message?board.id=170&message.id=146531&query.id=395443#M146531

In reply # 14 Christian's suggestion may help.

I am not sure if this will help in your case but I thought I'd point this out in the hopes it would help.

Trying to help,

Ben

[sparti]

hi there

Ben, thanks for the link. Christian's suggestion is right and describes a similar problem.

I solved the problem now on an other way. Each time before I change the visability of the scales I reset all settings to the default (startup) values by property nodes (YScale.Maximum, YScale.Minimum, All Visible...). Then I make the scales which I don't need unvisible, link the graphs to the prefered scales and set the Min/Max or autoscale.

Important: I got 4 scales on each side. When I want to use eg 2 scales on the left, I need to make visible scale number 1 and 2. Scales 3 and 4 can then be set to unvisible (in other words in an incrementing order).

Makeing scales visible and unvisible is a little bit nervous on the screen. So, during that process I bring a picture of the last waveform on the top of my screen and change to the graph view when all settings are done.

Now I got a really great waveform viewer with the possibility, scaling some graphs by autoscale, others by fixed scales, using up to 8 scales selectable on the left/right side, user definied colors, names and units.

Thank you all for taking part of my problem.

sparti