Expression nodes that allow comparisons

[paul_cardinale]

Allow comparison operators in expression nodes.  Input could be numeric or string, output would be boolean.

[RavensFan]

Why would you need this?  What is the benefit over normal LabVIEW comparison functions?

[paul_cardinale]

We don't really "need" any expression nodes at all.  But they can make our BDs cleaner.

For example, I would code x + 10 as:

not  as:

[RavensFan]

But expression nodes are quite a bit slower.

[AristosQueue (NI)]

> But they can make our BDs cleaner.

That's a matter of opinion. I happen to disagree. I find most math notation fairly distasteful to try to read. I mean, I have the skill, and I *can* do it for all sorts of arcane things, but even that basic notation there is less clear to me than the graphical notation of values going to operators. As I said, opinions vary. There are people who like writing whole applications in text. I prefer not to whenever possible.

[X.]

I personally much prefer this:

even though a dummy input is required (0 here, but obviously anything would work just fine), compared to that:

but it is true that my opinion is of little value, since I have to deal with this kind of formula on a regular basis...

I wonder what the Help for this node has in mind when it refers to "complicated" expressions:

Irony aside, regarding your proposal, you already have something  quite close with this:

The Expression Node in fact supports  (almost) all operators supported in the Formula Node, so there is quite some choice.

The problem you would have is that the "=" operator is an assignment operator in the syntax of the Formula/Expression Nodes, but isn't supported in the Expression Node (because it only supports one single variable). Forcing it to have a different meaning in the Expression Node would be confusing.

This being settled, how would you tell the node that you want a Boolean output rather than the natural numeric one? Some contextual menu option? I would argue that this is more pain than I would be willing to deal with.

Moreover, the syntax above also works with arrays:

 and clusters as well:

How would your new proposal handle this? Output a single value? An array, a cluster?

Strings? Seriously? It is my understanding that using strings is not recommended in LabVIEW...

[Darren]

Any idea that has received less than 3 kudos within 3 years after posting will be automatically declined.