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Will discuss the code in fragments

As usual, I will discuss the code in fragments. A complete listing of the program is presented in Listing 19 near the end of the module. Because of the similarity of Dsp028 with Dsp029 discussed earlier, the fragments for Dsp028 will be much larger and will be explained in much less detail.

Beginning of the class named Dsp028

The class definition begins in Listing 8 . For reasons that you already understand, this class implements the interface named GraphIntfc01.

Listing 8. Beginning of the class named Dsp028.
class Dsp028 implements GraphIntfc01{ final double pi = Math.PI;//for simplification//Begin default parameters int len = 400;//data length//Sample that represents zero time. int zeroTime = 0;//Low and high frequency limits for the // spectral analysis.double lowF = 0.0; double highF = 1.0;int numberSpectra = 5; //Frequencies of the sinusoidsdouble[] freq = {0.1,0.2,0.3,0.4,0.5};//Amplitudes of the sinusoids double[]amp = {60,70,80,90,100}; //End default parameters

The code in Listing 8 defines a set of default parameter values that are used in the event that a file named Dsp028.txt does not exist in the current directory.

Declare array variables

The code in Listing 9 declares several array variables that will be used to point to array objects whose purposes are explained in the comments.

Listing 9. Declare array variables.
//Following arrays will contain data that is // input to the spectral analysis process.double[] data1;double[] data2;double[] data3;double[] data4;double[] data5;//Following arrays receive information back // from the spectral analysis that is not used// in this program. double[]real; double[]imag; double[]angle; //Following arrays receive the magnitude// spectral information back from the spectral // analysis process.double[] magnitude1;double[] magnitude2;double[] magnitude3;double[] magnitude4;double[] magnitude5;

The constructor

The constructor for the class begins in Listing 10 . The constructor begins by getting the parameters from a file named Dsp028.txt . If that file doesn't exist in the current directory, default parameters are used.

Listing 10. Beginning of the constructor.
public Dsp028(){//constructor if(new File("Dsp028.txt").exists()){getParameters(); }//end if

Always processes five sinusoids

For simplicity, this program always processes five sinusoids, even if fewer than five were requested as the input parameter for numberSpectra . In that case, the extra sinusoids are processed using default values and simplyignored when the results are plotted.

Create the raw sinusoidal data

The code in Listing 11 instantiates array objects and creates the sinusoidal data upon which spectral analysis will be performed.

Listing 11. Create the raw sinusoidal data.
//First create empty array objects. double[]data1 = new double[len];double[] data2 = new double[len]; double[]data3 = new double[len];double[] data4 = new double[len]; double[]data5 = new double[len];//Now populate the array objects for(int n = 0;n<len;n++){ data1[n]= amp[0]*Math.cos(2*pi*n*freq[0]); data2[n]= amp[1]*Math.cos(2*pi*n*freq[1]); data3[n]= amp[2]*Math.cos(2*pi*n*freq[2]); data4[n]= amp[3]*Math.cos(2*pi*n*freq[3]); data5[n]= amp[4]*Math.cos(2*pi*n*freq[4]); }//end for loop

Questions & Answers

anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
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
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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
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Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
China
Cied
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
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many many of nanotubes
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Yasmin
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Cesar
I'm interested in nanotube
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Source:  OpenStax, Digital signal processing - dsp. OpenStax CNX. Jan 06, 2016 Download for free at https://legacy.cnx.org/content/col11642/1.38
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