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break;

end

end

LabVIEW MathScript supports the relational and logical operators listed below.

Relational Operators

Relational Operators
Symbol Meaning
<= less than equal
< less than
>= greater than equal
> greater than
== equal
~= not equal

Logical Operators

Logical Operators
Symbol Meaning
& AND
size 12{ \lline } {} OR
~ NOT

Programming in the labview mathscript window

The MathScript feature allows one to include .m files, which can be created using any text editor. To activate the LabVIEW MathScript interactive window, select Tools MathScript Window from the main menu. To open the LabVIEW MathScript text editor, click the Script tab of the LabVIEW MathScript Window (see [link] ). After typing the .m file textual code, save it and click on the Run script button (green arrow) to run it.

For instance, to write a program to compute the average (mean) of a vector x, the program should use as its input the vector x and return the average value. To write this program, follow the steps outlined below.

Type the following in the empty script:

x=1:10

L=length(x);

sum=0;

for j=1:L

sum=sum+x(j);

end

y=sum/L % the average of x

From the Editor pull-down menu, go to File Save Script As and enter average.m for the file name. Then click on the Run script button to run the program. [link] shows the LabVIEW MathScript interactive window after running the program.

LabVIEW MathScript Interactive Window after Running the Program Average

Sound generation

Assuming the computer used has a sound card, one can use the function sound to play back speech or audio files through its speakers. That is, sound(y,FS) sends the signal in a vector y (with sample frequency FS) out to the speaker. Stereo sounds are played on platforms that support them, with y being an N-by-2 matrix.

Try the following code and listen to a 400 Hz tone:

>>t=0:1/8000:1;

>>x=cos(2*pi*400*t);

>>sound(x,8000);

Now generate a noise signal by typing:

>>noise=randn(1,8000); % generate 8000 samples of noise

>>sound(noise,8000);

The function randn generates Gaussian noise with zero mean and unit variance.

Loading and saving data

One can load or store data using the commands load and save. To save the vector x of the above code in the file data.mat , type:

>>save data x

Note that LabVIEW MathScript data files have the extension .mat. To retrieve the data saved, type:

>>load data

The vector x gets loaded in memory. To see memory contents, use the command whos ,

>>whos

Variable Dimension Type x   1x8000 double array

The command whos gives a list of all the variables currently in memory, along with their dimensions. In the above example, x contains 8000 samples.

To clear up memory after loading a file, type clear all when done. This is important because if one does not clear all the variables, one could experience conflicts with other programs using the same variables.

Reading wave and image files

With LabVIEW MathScript, one can read data from different file types (such as .wav, .jpeg and .bmp) and load them in a vector.

To read an audio data file with .wav extension, use the following command:

>>[y Fs]=wavread(‘filename’)

This command reads a wave file specified by the string filename and returns the sampled data in y with the sampling rate of Fs (in hertz).

Questions & Answers

Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
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
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
sciencedirect big data base
Ernesto
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.
Bharti
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
Daniel
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
Maciej
characteristics of micro business
Abigail
for teaching engĺish at school how nano technology help us
Anassong
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
NANO
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
s.
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.
Tarell
what is the actual application of fullerenes nowadays?
Damian
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.
Tarell
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
Virgil
is Bucky paper clear?
CYNTHIA
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
NANO
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Harper
Do you know which machine is used to that process?
s.
how to fabricate graphene ink ?
SUYASH Reply
for screen printed electrodes ?
SUYASH
What is lattice structure?
s. Reply
of graphene you mean?
Ebrahim
or in general
Ebrahim
in general
s.
Graphene has a hexagonal structure
tahir
On having this app for quite a bit time, Haven't realised there's a chat room in it.
Cied
what is biological synthesis of nanoparticles
Sanket Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, An interactive approach to signals and systems laboratory. OpenStax CNX. Sep 06, 2012 Download for free at http://cnx.org/content/col10667/1.14
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