LabVIEW
Micro-Nuggets !!! ~~~~ Post 'em if you got 'em
@Darin.K wrote:
LabVIEW (forum) micronugget:
When suggesting new features to the LV Idea Exchange it is almost always a good idea to use less text and more descriptive picture. I can say with absolute certainty that the aforementioned idea would have received at least one more Kudos in its initial run if the picture had been shown in place of much of the text. Almost certainly many more.
Corollary: Pictures used in the idea pitch should probably be stripped down to the bare necesseties to focus attention on the elements of the idea itself.
Due to some of the mechanics of the Idea Exchange, it is probably too late to salvage RF's excellent suggestion.
Definitely true. Note that the idea was over 2 years ago when the idea exchange was still rather new. It just doesn't behave like the regular forums and I wasn't able to figure out the secret at that time to embed the images in the limited amount of time the forums gave to edit. (I'm not sure I wouldn't still have problems now embedding images in a new idea.)
Perhaps I'll either add another reply that embeds the images, or ask the moderator to modify the original idea for me to include the images.
One other problem with the idea exchange that we've discussed before is that older ideas tend to fall out of view and as the exchange gets more activity, new members may never get a chance to see the ideas that have been out there for awhile.
A very micro one! You can change the order in which the controls and indicators references appears in the Pnl:controls[] property by changing the tabbing order on the front panel (edit -> Set Tabbing Order).
Ben64
@Darin.K wrote:
Someday I'd like to do this and obliviate the need for the comments with the value.
No more Ctrl+E !
If you are not familiar with a functional global then read Ben's community nugget on Action Engines. A functional global is very similar to an action engine but it only has a set and get. It only stores data. If the VI operates on the data it is an action engine.
If you are still reading then I assume you know that a functional global is a VI with an uninitialized shift register on a single iteration while loop to store data. Inside the loop is a case structure that the shift register data is wired through.
But you don't really need the case structure or even the while loop. You can use a feedback node. This will only work with LabVIEW 2009 or later.
Now you need to define the data type by wiring a constant to the initializer terminal.
Right click on the feedback node and select Change Direction.
Now you need to right click on the feedback node again and select Show Enable Terminal.
Right click on the input and select create control. Right click on the output and select create indicator. Wire a boolean control to the enable and create error in and out controls. Wire up the connector pane and save your new functional global.
Are there any advantages? Well you can see all the code because you don't need a case structure. But the functional global is such a standard design that it shouldn't matter. Is it performance? No. A quick benchmark shows that the shift register slightly wins.
10 million sets and gets [Edit - 12.77 and 12.43, not 2.77 and 2.43]
- feedback node 12.77 seconds
- uninitialized shift register 12.43 seconds
So the advantage of using a feedback node for your functional globals may be just to show off 
I attached the benchmark code and the functional globals if anyone is interested.
One of the advantages is speed of creation. You can create these things a lot faster and time is one of the most important things on your CLD exam.
But it occured to me that you can go even faster by inserting the feedback node right into the wire.
