update closed chart

[Joseph_Loo]

I have Labview 8.5.1 running on windows XP. I am trying to generate a report based on a chart display that is closed with the append control image to report. Whenever I run the program with the chart display VI closed, it comes up with the default display. If I open the chart, the correct display shows up. I looked at the documentation and it seems to indicate that this is suppose to work without any problem. I have a similiar program with a graph and it works with no problem.

My primary aim is to have a stack chart for display because I am trying to show disimiliar values on a graph. I have a set of temperature running 0 to 900 deg, pressure 1000 to 10-6 torr, and current from 0 to 100. Stacking several graphs do not work very well, the graph display becomes out of sync with each other. Any suggestions are welcome.

[Ben]

IN general it is a good thing that LV does not use CPU to update images that are not being viewed.

In the past I have managed to work-around such issues by using an "invoke Node >>> Get Image" (wire the returned info to something so LV actually does the get image) after the update occurs.

Just trying to help,

Ben

[Joseph_Loo]

I agree with that idea, but I am trying to print the chart out.

I tried that with the chart. What I did is to invoke the method to fetch the image, save the image to disk, and append it to a report. The image was not updated. In fact append cotnrol image to report is suppose to do that. It did not though it worked for a graph.

[Adam_H]

Hi Joseph Loo,

I tried it on my end and did not have a problem with the chart updating when the front panel is minimized.  If you are talking about doing this with a graph that is in a subvi (and I think you are) then your assumptions are correct.  This will not work.  What you might be able to do is instead of graphing the data in your subVI send the data out and graph it in your main program.  This way you will always be updated.  If you do not always want to see the graph you can set the visibility to make it disappear when you do not need the information.    

Message Edited by Adam_H on 11-05-2008 08:24 AM

[Joseph_Loo]

The front panel requires a size of 1500x650. This seems to be the optimal size to print out on a landscape letter size paper with a left and right hand margin of 1inch. It seems the largest size I can print (regardless of the margins). I have to be careful, because if the size gets too large, the chart or graph will not plot the data correctly. 

In either case, the documentation needs to be updated with regard to charts and graphs. Graphs will work perfectly with the VI closed while charts will not. This has not been documented anywhere in my search.

[Adam_H]

Hi Joseph,

 I will see what I can do about getting some documentation out there about the issue. 

[Adam_H]

Hi All,

I have done a little more digging about the problem.  It turns out that this is not expected behavior.  This was reported to R&D (132503) for further investigation.  For the moment unfortunately you will need to have opened the called VI if you want to see the chart or use a graph.