Unknown graph cursor tool

[UNC_DC]

I'm hoping someone can identify a graph "tool" that's interfering with my LabVIEW program.  It's not on the normal graph palette and I can't find reference to it anywhere.  It activates seemingly on its own during runtime, and sticks around if I abort execution (its behavior appears to be coded into the graph itself).  I wasn't able to take a good screenshot of what the pointer looks like when the tool is active, so I've included a scaled-up drawing below (pointer is the black/white parts).

Some additional details:

- It usually activates when the mouse point hovers over one of the cursors on my XY graph (but only under certain conditions that are not 100% reproducible).  The graph cursors are free dragging, and the tool has only activated when I had more than 1 plot on the XY graph.

- If I click on a graph cursor when this tool is active and drag in either the +/- Y direction, the Y scale min/max values change to seemingly random values and the Y scale begins scrolling up.  Nothing happens if I move the cursor in purely the +/- X direction.

Much thanks in advance.

[DevonR]

Hi UNC_DC,

1. Could you please provide a screenshot of your front panel and block diagram? 

2. Also, can you please try right clicking the graph (before runtime) and select Visible Items»Cursor Legend?  What do you see there? Can you please provide a screenshot of that legend as well?

Here is some additional information on graph cursors:

http://zone.ni.com/reference/en-XX/help/371361H-01/lvhowto/adding_cursors_to_graphs/

Regards,

Devon R.

Applications Engineer

National Instruments

ni.com/support

[UNC_DC]

Hi Devon,

Unfortunately a screenshot of the block diagram wouldn't be sufficient (it's too big, and most of the code is in an event loop with many cases).  I can email you the entire VI though along with some data files to test it with (I didn't see an option to attach files through a private message).

There is nothing unusual about the cursor legend, and interacting with it doesn't change (or fix) the cursor state.

I recently learned something useful though: the mouse pointer (icon) in question is identical to the one that appears when dragging an annotation on the graph (or just hovering the mouse pointer over it).  However, the cursor state issue exists even when the graph has no annotations on it.

I'm fairly certain this is a bug.

[DevonR]

If you can attach your code that would definitely help us troubleshoot this issue.  In the meantime, can you please take a look at this KnowledgeBase Article on removing cursors from a graph?:

http://digital.ni.com/public.nsf/websearch/A6A7106671C65819862568E8007E0594?OpenDocument

Devon R.

Application Engineer

National Instrument

[UNC_DC]

Okay, I've been able to reproduce the problem consistently in a much simpler VI (attached).  It only contains is a single XY graph, with no code on the block diagram.  There's some data saved on the graph, and I put a bunch of cursors on it.  When I follow the steps below, I've been able to reproduce the issue 100% of the time.

I should note that I'm using LabVIEW 2014 Professional (64 bit) on Windows 7.

[UNC_DC]

I've resaved the VI for LabVIEW 2009 (attached).  I'm not sure if the issue will exist in previous versions of LabVIEW though...

[jeanlucpicard]

I tried zooming back and forth and could not reproduce it in LV 2012 32-bit on win7 64-bit. It always stayed the standard one, no matter how much I zoomed in

[UNC_DC]

Thanks for your input jeanlucpicard - I decided to try running the VI on a couple more computers here.  Two computers running LV 2014 64-bit both had this issue, but on another machine with LV 2012 64-bit I could not reproduce the problem after many attempts.

[johnsold]

LV2014, 64-bit on Mac OS X 10.9.5. I do not see the effect.

Lynn

[UNC_DC]

The bug has been confirmed by NI and is being tracked under CAR 403563.

Thanks to all for the help.