Problems with XY Graph "forgetting" plot properties

Question

I am having trouble with an XT Graph in my loop.
The graph has 10 plots which at any time can have anything from 0 to ~1000 points, often some plots will have significantly less ploints than others. There is a user selectable option to display all points or just the most recent set.
My problem is that I want the graph to reflect the input data by plotting a single point at the time of an update, so I have a string of points rather than a line.
When I right click the graph and go into properties, I change the point style to solid circle and turn off line interpolation. I then click save these values as default, and save the vi.
However, once I run the vi, the graph always reverts plots 1 to 9 (not plot 0, this stays as I want it) to have no points displayed and line interpolation on.
Has anyone had this problem before? Ho did you fix it?
I know it can be fixed, as I had this probelm a few months ago on a similar vi and after weeks of struggle I solved it, however I just cannot remember how I did it.
Thank you for any help, at the moment I can't post any code. Note that the data the graph shows is all perfectly fine, just the plot properties are being forgotten.
Solved!
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Answer 1

HI DarraghCorrigan,
In relation to the problem expressed in your initial post:
"once I run the vi, the graph always reverts plots 1 to 9 (not plot 0, this stays as I want it) to have no points displayed and line interpolation on"
This is due to a bug in the LabVIEW software whereby any changes that are made to the plot properties (e.g. to change the colour of a plot) will not be retained, except in plot 0 which is unaffected. Our R&D department are currently investigating this problem so that it can be fixed in future version of the software. The recommended workaround for this problem is to pragmatically set the plot settings at the beginning of the code using property nodes.
As I understand it, this is not the main problem that you are experiencing. If you set up the properties for a plot (using some of the described property nodes) which is subsequently removed or rewritten on an XY Graph, my understanding is that there is no way that LabVIEW can remember and retain these properties.
As you rightly suggested, one way of conveniently overcoming this problem would be to set default plot properties so that when you remove/rewrite a plot and then add it again, it will always default to those properties. Unfortunately, it is not currently possible to do this though it has been recommended as a product suggestion so it is a feature that is under consideration for implementation in future releases of LabVIEW.
I think the issue you need to be addressing is the fact that you are at some point resetting the graph by sending an empty array to it such that all of your properties are lost. If you can find and remove this section in your code, you should be able to overcome your problem.
I hope this helps.
Best Regards,
Christian Hartshorne
NIUK