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gamberetto

Negate option on Comparison functions

I would like to have the possibility to "negate" some comparison functions such as "Empty String/Path?". This can avoid to add the "Not" operator.

The picture below is a possible implementation. The dot on the input (on the output ok also) is showing the negation.

Labview Idea.png

This might be good to be implemented for the following functions:

Labview Idea 2.png

20 Comments
DavidBoyd
Active Participant

My first post was simply to show a corner-case visibility issue I'd noticed.  As far as the original IE subject...

 

I identify more than one concept being discussed here; the request to have the logical complement as a configurable option for several nodes with Boolean outputs, and the more general discussion of the existing bubble's readability.

 

I would thumbs-down the original request as it stands, if purely for the jarring syntax (as shown) of a negation/inversion bubble on the input side of a "test-for" node that takes something other than Boolean - like string or path.  Or, for the isNAN, a repurposing - the bubble on input implies mathematical negation on a compound arithmetic node with a numeric input, but on the isNAN it means logical inversion of the test result.

 

Opinion: The language is rich enough, just use the logical Not node where needed, it's far less likely to be missed in casual review.

 

Now, as concerns the pesky little bubbles themselves:

- please DON'T fill them in - that is contrary to my lifetime experience of reading digital logic schematics

- find some subtle way for the NI design folk to enhance them... just a little... so they don't get lost between the monitor and my old eyes

- I'd even vote up changing the Not node appearance to move the bubble to the output side.  That feels far more consistent to me with the appearance of the NAND, NOR, Not-XOR (I was taught to call it "coincidence"), and the aforementioned logic schematics.

 

Dave

David Boyd
Sr. Test Engineer
Abbott Labs
(lapsed) Certified LabVIEW Developer
wiebe@CARYA
Knight of NI

Why not include the In Range And Coerce?

JÞB
Knight of NI

I don't mind the idea.  certainly the OUTPUT needs to show the negated glyph rather than the input.  I'n not sure it applies to Lexical Class? or any other integer output. (David, a Tue constant is pretty easy to read Smiley Wink maybe not the best example)

 

I would even allow it on  Bool to 0-1's input (beats decrements + negate on the output) but limit it to comparisons and Boolean.  We wouldn't want that little glyph to become "Not Timed Out?"  People will start hunting down and shooting LabVIEW developers.


"Should be" isn't "Is" -Jay
TomOrr0W
Member

Looking at the comments on this idea, I ended up searching invert, negate, bubble, and circle (skipping anything that was already marked duplicate).  I figured I might as well link the related ideas.

 

Strongly Related:

https://forums.ni.com/t5/LabVIEW-Idea-Exchange/Invert-Option-in-all-Boolean-Terminals/idi-p/1281058

https://forums.ni.com/t5/LabVIEW-Idea-Exchange/Array-String-not-empty-function/idi-p/3163821

https://forums.ni.com/t5/LabVIEW-Idea-Exchange/Offer-a-Positive-Logic-Alternative/idi-p/1022834

 

Related:

https://forums.ni.com/t5/LabVIEW-Idea-Exchange/Negate-input-on-boolean-functions/idi-p/1084159

https://forums.ni.com/t5/LabVIEW-Idea-Exchange/Invertable-case-selector/idi-p/2320108

https://forums.ni.com/t5/LabVIEW-Idea-Exchange/Shortcut-to-Invert-Input-Output-in-Compound-Arithmeti...

https://forums.ni.com/t5/LabVIEW-Idea-Exchange/Correct-the-quot-not-quot-symbol-by-removing-the-inve...

https://forums.ni.com/t5/LabVIEW-Idea-Exchange/Automatically-invert-compound-arithmetic-inputs-when-...

https://forums.ni.com/t5/LabVIEW-Idea-Exchange/Invert-signal-going-into-a-select-VI/idi-p/2224232

https://forums.ni.com/t5/LabVIEW-Idea-Exchange/General-Comparison-Operator-as-an-Express-VI/idi-p/12...

https://forums.ni.com/t5/LabVIEW-Idea-Exchange/Simplifying-Boolean-expressions/idi-p/1890963

 

A couple people mentioned making inversion bubbles more visible:

https://forums.ni.com/t5/LabVIEW-Idea-Exchange/Enlarge-the-Invert-Circles/idi-p/1023748

https://forums.ni.com/t5/LabVIEW-Idea-Exchange/Replace-the-Invert-Circles-in-Compound-Arithmetic-Nod...

https://forums.ni.com/t5/LabVIEW-Idea-Exchange/Compound-Arithmetic-with-inverted-input-should-be-eas...

littlesphaeroid
Active Participant

In gamberetto's post the invert indication is shown on the left of the primitive. However, I think he means to put the invert circle on the right (the Boolean is inverted, not the input value).

_____________
Creator of the BundleMagic plugin for LabVIEW!
gamberetto
Member

I totally agree with all of you writing that the best placement for the dot is on the right

Thanks for highlighting so.

Dot on the rightDot on the right

Bob_Schor
Knight of NI

Since the only logical place to add a "Not" Boolean function to, say, "Empty String or Path", is to the output of the function, the "not" symbol (the little circle already in use for compound arithmetic is fine with me) must (logically) be on the right (output) side of the function.  I agree that saying "not not a Number" is a mouthful, but don't two Wrongs make a Right?  (or do I need to negate that statement?  I'm so confused ...)

 

Bob Schof

JÞB
Knight of NI

A few issues:

 

Negating the output of most logical Operations is moot.  Read your tautologies 1-12. Not on "Is" comparisons sounds great except for  "Is NaN" since,  NaN must fail all comparisons "Is NaN" is defined.  "Is Not NaN" or "Is NaN NOT" are more confusing than NaN itself!  Hence, Unless the documentation is clear and explicit in all localized languages.  I'd use a merge vi rather than a circle on the output.  Or, my high school logic notes.


"Should be" isn't "Is" -Jay
d.w.b
Member

This 2017 idea should be marked as a duplicate of the following 2010 idea so users can concentrate kudos and comments on just one thread. Besides, Invert is precedent over Negate: https://forums.ni.com/t5/LabVIEW-Idea-Exchange/Invert-Option-in-all-Boolean-Terminals/idi-p/1281058

jenniferbni
NI Employee (retired)
Status changed to: Duplicate