delete plots from waveform graph

[Kenneth]

RavensFan,

thanks for the reply.  I did try the list recommendations.

From the first example of combining two signals into the graph:  I ran the example with two signals clustered for the graph terminal.  Saw two graphs, two items in the plot legend, and two plots in the graph property page. 

Even after wiring fewer signals to the terminal, I still saw all ten (10) plots listed in the property page.

[RavensFan]

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@Kenneth wrote:

Even after wiring fewer signals to the terminal, I still saw all ten (10) plots listed in the property page.

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Did you Run the VI again with the fewer signals going to the graph.  Just wiring fewer signals in without running it doesn't change the data that it currently in the graph.  Running the VI sends the graph new data with the fewer signals, until then, the graph contains the older data (with more signals) from the last time you ran it.

Also, to be sure, you are working with a graph and not a chart?

[Kenneth]

RF, thanks for the suggestions.  Waveform graph: check, run the VI: check. 

To be clear, this appears to be a configuration cosmetic issue.  I see the correct number of plots in the graph.  I programmatically change the number of plots visible in the legend.  But the configuration of the graph shows extra plots on the property page, "Plots."  Please try the following steps to confirm the behavior.

To recreate this issue (LV 2009):

1. Create a new VI

2. Place a Waveform Graph on the panel

3. On the diagram, drop a generate signal (I like sine) in a FOR loop and set the count terminal to generate 4 signals.  I differentiate the signals by wiring the iteration terminal (+1) to the frequency input of the function generator.

4. From the signal output of the Generate signal function, wire that out of the FOR loop to the graph's terminal.

Run the VI

A. On the panel, observe four plots are graphed and only one plot is displayed in the legend.

B. Increase the plot legend to show 10 names

C. Reduce the plot legend to show only 4 names

D. Run the VI again, if you prefer

E. Open the property page for the graph, view the Plots tab and open the ring for the plots.

At step E, I still see 10 plots, not the 4 plots that I generated.

If I expand the plot legend to show 18 names (step B), then I see that number of entries in the ring in step E.

[RavensFan]

The detail about changing the size of the plot legend is an important one that you hadn't mentioned before.  I had done what you said with a for loop and the +1 to increment the i counter, but I fed it into amplitude of the sine wave function.  But I had not changed the size of the plot legend.  In LV2010, the number of plots shown in the property dialog AFTER running matched the number of iterations of my For Loop.

Now seeing your mention of changing the size of the plot legend, I tried again by manually resizing it.  I do see that the extra plots will remain in the dialog box even after you reduce the size of the plot legend and run the VI with fewer plots generated.  Basically, the number of plots shown in the dialog will be the larger value of either the number of plots fed to the graph at the last running of the VI, or the largest size that the plot legend as ever been.

I can understand why the dialog box shows more plots when you resize the legend, even when you don't plot data, there have to be properties for the extra plots that are appearing in the legend.  But it seems to permanently stick the existence and properties of these extra plots in the graph even when they aren't needed anymore.

I don't know whether this can be classified as a bug, or just some unexpected and possibly undesirable behavior.

If you delete the graph and wire in a new graph, then you've effectively set things back to a default set of properties.  But my question is having the extra plots in the property dialog a big issue for you?  It is something that only you would ever see as a programmer when you use that part of the property dialog, and not something a user of your application would ever see.

[Kenneth]

As this is a programming configuration issue, the user will never see this issue directly. 

As for recreating the Waveform graph from scratch, this graph has been tweaked colors, plot attributes, cursors, annotations, backgrounds per customer requirements.  Not a severe issue to warranty redoing all of that work from scratch or from VI Server.

[RavensFan]

Maybe someone from NI will see this message thread and can comment on the behavior.  If there is some other way around it, I can't see it at this time.

[opejumeys]

I have also found some issues with the graph Legend not removing previous plots.  Attached is a VI that describes the problem.  This has also been submitted directly to NI and they are working on a fix.

[nickbike]

Please, please fix this  I have a waveform graph that I have nicely formatted the way I want it. I use property nodes to do a lot of other things with the graph including cursors and changing the size of the legend to only show the plots I want. I accidentally wrote a whole bunch of plots to the graph and there's now almost 800 plots in properties dialog. I've since fixed the problem with writing so many plots to the graph, however, the VI hangs because of the overhead of having so many plots in the graph. I can't delete the plots and the only way to clear this out is to delete my waveform graph (and all it's property nodes) and start over. This has really put me in a bind.  

[opejumeys]

You can use explicit property nodes, where you just need to change the reference rather than implicit property nodes that are tied to a specific graph.  This would make it significantly easier to change out the graph when/if you need to.

[arnemad]

Hi

I have the exact same issue as described above.

For me the problem is that I want to autosize my legend according to the longest plot name. And if the number of inputs to the graph was larger and with longer names on the previous run, the autosizing will be done according to previous plot names.

Arne M