Need suggestions for highlighting plot details in strip chart graph

[Vrmithrax]

Hoping someone has some good suggestions or solutions for me...

I've got a user interface that is tied to a cRIO control system, showing sensor data and other feedback in real-time.  The user interface shows multiple graphs (up to 4) that are tracking individual position sensors (one for each piece of hardware monitored) and displaying the amount of deflection being experienced.  The problem is that not all of the hardware is active during each control process, so it becomes very hard to track how relevant the graphs are at any given moment.  My ideal solution would be to change the color of the plot line to indicate when it is active and when it is idle in the process, but programatically changing the color changes the entire plot, not just the relative portion I want.  That option doesn't work too well at conveying the information I want when they do a screen or graph print, it is still impossible to determine which items were active and when.  Disappointing, but I guess I can understand why it's done that way (if you have to constantly track color too for every data point you could really impact graph overhead).

So, I'm looking for other alternatives.  Anyone found a way around this limitation, or have any suggestions that might let me provide a nice highlight or some way to make the "active" portions of these strip charts stand out?

[0utlaw]

Hello Vrmithrax,

There is a way to achieve this visual effect using two contiguous plots on the chart, but be careful how you handle the data- attempting to export from the chart will give garbled results.  There's an example that demonstrates this being done for a threshold here:

Community Example: Single Plot with Color Change at Threshold

https://decibel.ni.com/content/docs/DOC-13145

Something similar could be done with time slices rather than thresholding.

Regards,

[Vrmithrax]

Hi Tom,

That is interesting alternative...  I had found another similar method using the NaN and stacked plots method, but this one is a little more elegant.  My only worry is what will happen if I am also continuously logging to a file for later review (if the equipment experiences catastrophic failure they need to go back and analyze what happened prior to the incident).  The logging portion is something I am fighting with currently, trying to work out how to implement it properly.

Just starting to wish LabVIEW had a built-in option for changing colors point by point...  It would make my life so much easier!

Also, an interesting thought:  maybe a method to change a block of the background color on a strip chart to "highlight" a specific range of data?

[0utlaw]

Hi Vrmithrax,

With a few tweaks to plot size, color, and point style, you could have something like this:

You'll just need to track which plot you want to emphasize and assign that plot's current value to the "highlight" plot.  Otherwise plot NaN.  This won't affect the original data, so there should be less to try and keep track of elsewhere in the code.

Regards,