LabVIEW Wiki - User contributions [en]

Property node

2023-08-06T03:22:03Z

Ederson:

{{LabVIEW Palette Object Information|palette=Functions Palette/Programming/Application Control{{!}}Application Control palette|type=function|icon=Property node.png}}

'''Property Nodes''' are nodes that you can use in your '''Block Diagram''' to GET or SET properties on a local or remote application, VIs, and objects. Property Nodes allow you to programmatically control the properties of a '''Front Panel''' object, for example: color, visibility, position, behavior, etc.

You can use '''Property Nodes''' in two ways: Explicit that you choose what the Control/Indicator it referees to, or Implicit that is the case when you use a Reference wired to the Property Node that indicates what is LabVIEW item you referee.

[[File:Pl.png]]

Clicking on the Property, you can choose what Property you want to '''Read/Write'''. You choose if the Property Node is '''Read''' or '''Write''' by right-clicking on the Property Node selecting '''Change to Read''' or '''Change to Write'''. By default, the Property Node is set to '''Read'''.

==Performance Issues==
'''Property Nodes''' should be used carefully. That's because it is executed in the user-interface thread. Using '''Property Nodes''' indiscriminately in your code affects its performance because Block Diagram waits while properties execute in the user-interface. If your Property Node runs in a SubVIs, it makes the SubVI front panel to be loaded into memory. Try to limit the number of Property Nodes used in your application.

One Property that you should avoid is the '''Value property'''. You should always use Controls/Indicator and its wires to Read/Write their values. If it is not possible to reach the terminal or wire in your code, use Queues, Notifiers, and even Local Variables to that, but '''never''' use '''Value property'''.

[[File:Captura de tela 2023-08-06 002028.png]]

File:Captura de tela 2023-08-06 002028.png

2023-08-06T03:21:36Z

Ederson:

avoid Value property

Property node

2023-08-05T22:51:21Z

Ederson:

File:Property node.png

2023-08-05T22:48:26Z

Ederson:

property node

File:Pl.png

2023-08-05T22:36:09Z

Ederson:

Property Node Implicit and Explicit

Local Variable

2023-08-05T22:12:30Z

Ederson:

{{LabVIEW Palette Object Information|palette=Functions Palette/Programming/Structures{{!}}Structures palette|type=function|icon=Functions Palette - Programming - Structures - Local Variable.png}}

Use '''Local Variables''' to read or write to one of the [[Control]]s or [[Indicator]]s on the [[Front Panel]] of a [[VI]].

== Usage ==

Stopping both parallel loops using the same Stop Button.

[[File:Parallel loop using local variables.png]]

It is necessary to change Stop Button Control mechanical action from '''Latch'''... to '''Switch'''...

== Best practice ==
Using ''Local Variables'' breaks data flow execution. It is useful when it is not possible to pass data through wires, like parallel processes. In this case, the use of ''Local variables'' can be a solution. However, you should be careful when using this resource because it can generate unexpected behavior when you write values in multiple places in your code.
A good rule to follow when you use ''Local Variable'' is: ''One Write, Multiple Reads''.

Example of avoiding Local Variables:
If you have a State Machine design pattern and lots of Local Variables being read and written through the Cases is: ''Change local variables instances for a wire using a Shift Register to update the value when is necessary''. See the picture below:

[[File:Local2.png]]

== History ==
{{ambox|text=History information is needed. What changes have occurred over previous versions?}}
{| class="wikitable"
! Version
! Change(s)
|-
|[[File:LV2018.png|frameless|border|64x64px|LabVIEW 2018|link=LabVIEW 2018]]
|More info to come.
|}
== See Also ==

* https://labviewwiki.org/wiki/Race_condition

== External Links ==
{{ambox|text=Add links to external resources that would also help.}}

[[Category:Structures Palette]]

SubVI

2023-08-05T19:08:51Z

Ederson:

'''SubVIs''' are [[VI]]s that are called from another [[VI]]. This is accomplished by:
# Connecting [[Control|controls]] and [[Indicator|indicators]] to a [[VI]]'s [[Connector Pane]]
# Dropping that [[VI]] on a Block Diagram of another [[VI]]
# Attaching [[Wire]]s to its inputs and outputs
There is no difference between a [[VI]] and a SubVI except the relationship in [[Calling Heirarchy]].

== Usage ==
'''SubVIs''' work as functions on textual programming languages. Instead of having the same code writing in many parts of the code, we put it in [[VI]]'s so it can be called every time we need.

[[File:SubVIs.png]]

== Best Practices ==

Create a VI description at VI Properties -> Documentation. The description appears in the Context Help when you hover on the VI in the block diagram.

[[File:Context help.png]]

For more '''Best Practices''' for '''SubVIs''' use, look at [[Icon Editor]] and [[Connector Pane]] pages.

[[Category:Node]]

File:Context help.png

2023-08-05T19:07:24Z

Ederson:

Context help meassge

File:SubVIs.png

2023-08-05T18:53:42Z

Ederson:

A subVI performing conversion from Celsius degree temperature to Fahrenheit degree temperature.

Local Variable

2023-07-25T23:14:35Z

Ederson: /* Best practice */

{{stub}}
{{TOCright}}
{{LabVIEW Palette Object Information|palette=Functions Palette/Programming/Structures{{!}}Structures palette|type=function|icon=Functions Palette - Programming - Structures - Local Variable.png}}

Use '''Local Variables''' to read or write to one of the [[Control]]s or [[Indicator]]s on the [[Front Panel]] of a [[VI]].

== Usage ==

Stopping both parallel loops using the same Stop Button.

[[File:Parallel loop using local variables.png]]

It is necessary to change Stop Button Control mechanical action from '''Latch'''... to '''Switch'''...

== Best practice ==
Using ''Local Variables'' breaks data flow execution. It is useful when it is not possible to pass data through wires, like parallel processes. In this case, the use of ''Local variables'' can be a solution. However, you should be careful when using this resource because it can generate unexpected behavior when you write values in multiple places in your code.
A good rule to follow when you use ''Local Variable'' is: ''One Write, Multiple Reads''.

Example of avoiding Local Variables:
If you have a State Machine design pattern and lots of Local Variables being read and written through the Cases is: ''Change local variables instances for a wire using a Shift Register to update the value when is necessary''. See the picture below:
[[File:Local2.png|thumb|left|891x367px]]

== History ==
{{ambox|text=History information is needed. What changes have occurred over previous versions?}}
{| class="wikitable"
! Version
! Change(s)
|-
|[[File:LV2018.png|frameless|border|64x64px|LabVIEW 2018|link=LabVIEW 2018]]
|More info to come.
|}
== See Also ==

https://labviewwiki.org/wiki/Race_condition

== External Links ==
{{ambox|text=Add links to external resources that would also help.}}

[[Category:Structures Palette]]

File:Local2.png

2023-07-25T23:07:53Z

Ederson:

Using wires instead of locals

Local Variable

2023-07-15T14:11:05Z

Ederson:

{{stub}}
{{TOCright}}
{{LabVIEW Palette Object Information|palette=Functions Palette/Programming/Structures{{!}}Structures palette|type=function|icon=Functions Palette - Programming - Structures - Local Variable.png}}

Use '''Local Variables''' to read or write to one of the [[Control]]s or [[Indicator]]s on the [[Front Panel]] of a [[VI]].

== Usage ==

Stopping both parallel loops using the same Stop Button.

[[File:Parallel loop using local variables.png]]

It is necessary to change Stop Button Control mechanical action from '''Latch'''... to '''Switch'''...

== Best practice ==
Using ''Local Variables'' breaks data flow execution. It is useful when it is not possible to pass data through wires, like parallel processes. In this case, the use of ''Local variables'' can be a solution. However, you should be careful when using this resource because it can generate unexpected behavior when you write values in multiple places in your code.
A good rule to follow when you use ''Local Variable'' is: ''One Write, Multiple Reads''.

== History ==
{{ambox|text=History information is needed. What changes have occurred over previous versions?}}
{| class="wikitable"
! Version
! Change(s)
|-
|[[File:LV2018.png|frameless|border|64x64px|LabVIEW 2018|link=LabVIEW 2018]]
|More info to come.
|}
== See Also ==

https://labviewwiki.org/wiki/Race_condition

== External Links ==
{{ambox|text=Add links to external resources that would also help.}}

[[Category:Structures Palette]]

List of LabVIEW Champions

2023-07-10T18:16:49Z

Ederson:

{{see also|LabVIEW Champion|LabVIEW Champions program FAQ}}
Complete List at NI.com: [https://forums.ni.com/t5/LabVIEW-Champions-Directory/tkb-p/3012 LabVIEW Champions]

{| class="wikitable sortable"
|-
! Name
! Tenure
! Home
|-
| [[Albert Geven (LabVIEW Champion)|Albert Geven]]
| 2005-Present
| Netherlands
|-
| [[Alessandro Ricco (LabVIEW Champion)|Alessandro Ricco]]
| 2005-Present
| Italy
|-
| [[André Manzolli (LabVIEW Champion)|André Manzolli]]
| 2005-Present
| Brazil
|-
| [[Ben Rayner (LabVIEW Champion)|Ben Rayner]]
| 2005-Present
| United States
|-
| [[Bill Meier (LabVIEW Champion)|Bill Meier]]
| 2010-Present
| United States
|-
| [[Bogdan Iwinski (LabVIEW Champion)|Bogdan Iwinski]]
| 2010-Present
| Poland
|-
| [[Brett Percy (LabVIEW Champion)|Brett Percy]]
| 2005-Present
| Australia
|-
| [[Bruce Ammons (LabVIEW Champion)|Bruce Ammons]]
| 2005-Present
| United States
|-
| [[Buddy Haun (LabVIEW Champion)|Buddy Haun]]
| 2008-Present
| United States
|-
| [[Charles Ghommidh (LabVIEW Champion)|Charles Ghommidh]]
| 2005-Present
| France
|-
| [[Chris Cilino (LabVIEW Champion)|Chris Cilino]]
| 2017-Present
| United States
|-
| [[Chris Roebuck (LabVIEW Champion)|Chris Roebuck]]
| 2013-Present
| United Kingdom
|-

| [[Christian Altenbach (LabVIEW Champion)|Christian Altenbach]]
| 2005-Present
| United States
|-
| [[Christian Butcher (LabVIEW Champion)|Christian Butcher]]
| 2021-Present
| Japan
|-
| [[Christophe Salzmann (LabVIEW Champion)|Christophe Salzmann]]
| 2010-Present
| United States
|-
| [[Christopher G. Relf (LabVIEW Champion)|Christopher G. Relf]]
| 2005-Present
| United States
|-
| [[Dany Allard (LabVIEW Champion)|Dany Allard]]
| 2013-Present
| Canada
|-
| [[Darin Kinion (LabVIEW Champion)|Darin Kinion]]
| 2012-Present
| United States
|-
| [[David Thomson (LabVIEW Champion)|David Thomson]]
| 2005-Present
| United States
|-
| [[Dennis Knutson (LabVIEW Champion)|Dennis Knutson]]
| 2005-Present
| United States
|-
| [[Ed Dickens (LabVIEW Champion)|Ed Dickens]]
| 2005-Present
| United States
|-
| [[Ederson Ramalho (LabVIEW Champion)|Ederson Ramalho]]
| 2023-Present
| Brazil
|-
| [[Fabiola De la Cueva (LabVIEW Champion)|Fabiola De la Cueva]]
| 2012-Present
| United States
|-
| [[Felipe Pinheiro Silva (LabVIEW Champion)|Felipe Pinheiro Silva]]
| 2021-Present
| Brazil
|-
| [[Francois Normandin (LabVIEW Champion)|Francois Normandin]]
| 2019-Present
| Canada
|-
| [[Gaurav Kulkarni (LabVIEW Champion)|Gaurav Kulkarni]]
| 2013-Present
| India
|-
| [[Jack Dunaway (LabVIEW Champion)|Jack Dunaway]]
| 2010-Present
| United States
|-
| [[Jeff Bohrer (LabVIEW Champion)|Jeff Bohrer]]
| 2012-Present
| United States
|-
| [[Jim Kring (LabVIEW Champion)|Jim Kring]]
| 2005-Present
| United States
|-
| [[Joe Hoskins (LabVIEW Champion)|Joe Hoskins]]
| 2010-Present
| United States
|-
| [[Joerg Hampel (LabVIEW Champion)|Joerg Hampel]]
| 2018-Present
| Austria
|-
| [[Jonathon Green (LabVIEW Champion)|Jonathon Green]]
| 2012-Present
| Australia
|-
| [[Justin Goeres (LabVIEW Champion)|Justin Goeres]]
| 2012-Present
| United States
|-
| [[Kabul Maharjan (LabVIEW Champion)|Kabul Maharjan]]
| 2019-Present
| United Kingdom
|-
| [[Kevin Shirey (LabVIEW Champion)|Kevin Shirey]]
| 2022-Present
| United States
|-
| [[Leigh Christian (LabVIEW Champion)|Leigh Christian]]
| 2010-Present
| United States
|-
| [[Marcus Johnson (LabVIEW Champion)|Marcus Johnson]]
| 2013-Present
| Sweden
|-
| [[Mark Balla (LabVIEW Champion)|Mark Balla]]
| 2010-Present
| United States
|-
| [[Mark Ridgley (LabVIEW Champion)|Mark Ridgley]]
| 2013-Present
| United States
|-
| [[Mark Yedinak (LabVIEW Champion)|Mark Yedinak]]
| 2010-Present
| United States
|-
| [[Michael Aivaliotis (LabVIEW Champion)|Michael Aivaliotis]]
| 2005-Present
| Canada
|-
| [[Mike Porter (LabVIEW Champion)|Mike Porter]]
| 2008-Present
| United States
|-
| [[Muthuraman Sudalaimuthu (LabVIEW Champion)|Muthuraman Sudalaimuthu]]
| 2013-Present
| India
|-
| [[Nancy Hollenback (LabVIEW Champion)|Nancy Hollenback]]
| 2008-2010<ref>In 2010, Nancy joined NI.</ref>
| United States
|-
| [[Navin Subramani (LabVIEW Champion)|Navin Subramani]]
| 2021-Present
| United States
|-
| [[Norm Kirchner (LabVIEW Champion)|Norm Kirchner]]
| 2008-2008<ref>Months after becoming a Champion, Norm joined NI.</ref>
| United States
|-
| [[Quentin "Q" Alldredge (LabVIEW Champion)|Quentin "Q" Alldredge]]
| 2018-Present
| United States
|-
| [[Parag Deshpande (LabVIEW Champion)|Parag Deshpande]]
| 2012-Present
| India
|-
| [[Pavan Bathla (LabVIEW Champion)|Pavan Bathla]]
| 2007-Present
| United States
|-
| [[Piotr Maj (LabVIEW Champion)|Piotr Maj]]
| 2012-Present
| Poland
|-
| [[Putnam W. Monroe Jr. (LabVIEW Champion)|Putnam W. Monroe Jr.]]
| 2005-Present
| United States
|-
| [[Ray Robichaud (LabVIEW Champion)|Ray Robichaud]]
| 2005-Present
| Canada
|-
| [[Richard Sorrells (LabVIEW Champion)|Richard Sorrells]]
| 2013-Present
| United States
|-
| [[Rick Beauchaine (LabVIEW Champion)|Rick Beauchaine]]
| 2005-Present
| United States
|-
| [[Richard Thomas (LabVIEW Champion)|Richard Thomas]]
| 2012-Present
| England
|-
| [[Roger Isaksson (LabVIEW Champion)|Roger Isaksson]]
| 2013-Present
| Sweden
|-
| [[Rolf Kalbermatter (LabVIEW Champion)|Rolf Kalbermatter]]
| 2010-Present
| Netherlands
|-
| [[Sam Roundy (LabVIEW Champion)|Sam Roundy]]
| 2019-Present
| United States
|-
| [[Samuel James (LabVIEW Champion)|Samuel James]]
| 2012-Present
| India
|-
| [[Samuel Taggart (LabVIEW Champion)|Samuel Taggart]]
| 2018-Present
| United States
|-
| [[Saverio Mercurio (LabVIEW Champion)|Saverio Mercurio]]
| 2010-Present
| United States
|-
| [[Scott Hannahs (LabVIEW Champion)|Scott Hannahs]]
| 2005-Present
| United States
|-
| [[Shane O'Neill (LabVIEW Champion)|Shane O'Neill]]
| 2010-Present
| Switzerland
|-
| [[Steve Watts (LabVIEW Champion)|Steve Watts]]
| 2013-Present
| United Kingdom
|-
| [[Tim Robinson (LabVIEW Champion)|Tim Robinson]]
| 2013-Present
| United States
|-
| [[Tomi Maila (LabVIEW Champion)|Tomi Maila]]
| 2007-Present
| Finland
|-
| [[Tom McQuillan (LabVIEW Champion)|Tom McQuillan]]
| 2021-Present
| United Kingdom
|-
| [[Urs Lauterburg (LabVIEW Champion)|Urs Lauterburg]]
| 2005-Present
| Switzerland
|-
| [[Yair Neeman (LabVIEW Champion)|Yair Neeman]]
| 2007-Present
| Israel
|-
| [[Zbigniew Sobków (LabVIEW Champion)|Zbigniew Sobków]]
| 2005-Present
| Poland
|}

<references />

[[Category:LabVIEW Champions]]
[[Category:Lists]]

Local Variable

2023-07-09T23:31:36Z

Ederson: /* See Also */

Local Variable

2023-07-09T23:30:44Z

Ederson: /* Usage */

Local Variable

2023-07-09T23:20:17Z

Ederson: /* Usage */

Local Variable

2023-07-09T23:19:41Z

Ederson: /* Usage */

File:Parallel loop using local variables.png

2023-07-09T23:16:48Z

Ederson:

Used to stop both loops with the same Stop Button Control.