Matrix in feedback node

[Lennartw]

Hi, I'm currently using Labview 2013 and I am trying to place a matrix in a feedback node. It seems like I found a bug, because it does work for a feedback loop.

I wanted to use a feedback node to prevent labview from calculating the same matrix every loop.

Am I doing something wrong here? Or is this an issue with Labview?

[GerdW]

Hi Lennart,

with LV2009 I can create a working snippet:

What's the point of using a shift register or FeedbackNode in your example? When the values don't change you don't need them!

Interesting side effect: the wires are placed different at the ADD node inputs compared to "usual" wires (like scalars or arrays). They are shifted 3 pixels up/down…

[Munna232]

Hi GerdW,

I checked your snippet in 2014. I also got same kind of error.

[P@Anand]

I am seeing the same issue in LabVIEW 2012. 

[GerdW]

Same issue in LV2011…

More interesting side effects:

Apart from visual glitches LabVIEW will create the wrong indicator when right-clicking the (apparently) scalar result wire of the left ADD node…

Edit:

The result of the snippet for two matrices of 2×2 "zero" elements is "2.16178E-314" when "x+y" indicator is connected to left ADD node. When adding zero with the right ADD node you receive "3.97926E-316". So adding zero (or creating data copies by adding other functions) will change the result…

Looks like a compiler error to me…