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The power of LabVIEW lies in the hierarchical nature of the VI. After you create a VI, you can use it on the block diagramof another VI. There is no limit on the number of layers in the hierarchy. Using modular programming helps you manage changesand debug the block diagram quickly.

A VI within another VI is called a subVI. A subVI corresponds to a subroutine in text-based programming languages. When youdouble-click a subVI, a front panel and block diagram appear, rather than a dialog box in which you can configure options. Thefront panel includes controls and indicators that might look familiar. The block diagram includes wires, front panel icons,functions, possibly subVIs, and other LabVIEW objects that also might look familiar.

The upper right corner of the front panel and block diagram displays the icon for the VI. This icon is the same as the iconthat appears when you place the VI on the block diagram.

Icon and connector pane

After you build a front panel and block diagram, build the icon and theconnector pane so you can use the VI as a subVI. Every VI displays an icon, such as the one shown in , in the upper right corner of the front panel and block diagram windows. An icon is a graphicalrepresentation of a VI. It can contain text, images, or a combination of both. If you use a VI as a subVI, the iconidentifies the subVI on the block diagram of the VI. You can double-click the icon to customize or edit it.

You also need to build a connector pane, shown in , to use the VI as a subVI. The connector pane is a set of terminals that correspond to the controls andindicators of that VI, similar to the parameter list of a function call in text-based programming languages. Theconnector pane defines the inputs and outputs you can wire to the VI so you can use it as a subVI. A connector pane receivesdata at its input terminals and passes the data to the block diagram code through the front panel controls and receives theresults at its output terminals from the front panel indicators.

As you create VIs, you might find that you perform a certain operation frequently. Consider using subVIs or loops toperform that operation repetitively. For example, the block diagram in contains two identical operations.

You can create a subVI that performs that operation and call the subVI twice. The example in calls the Temperature VI as a subVI twice on its block diagram and functions the same as the previous blockdiagram.You also can reuse the subVI in other VIs. Refer to Repetition and Loops for more information about using loops to combine common operations.

Refer to the LabVIEW Basics II: Development Course Manual for more information about application development. The following pseudo-code and block diagramsdemonstrate the analogy between subVIs and subroutines.

Function Code Calling Program Code
main {average (point1, point2, pointavg)}
function average (in1, in2, out){ out = (in1 + in2)/2.0;}
SubVI Block Diagram CallingVI Block Diagram

Questions & Answers

what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
scanning tunneling microscope
how nano science is used for hydrophobicity
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
what is differents between GO and RGO?
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
How can I make nanorobot?
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
how can I make nanorobot?
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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