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Perform the spectral analysis

The code in Listing 12 creates array objects to receive the results and calls the static transform method of the forwardRealToComplex01 class five times in succession to perform the spectral analysis on each of the five sinusoids.

(I will explain the transform method that performs the spectral analysis shortly.)

Only the magnitude data is displayed by this program. Therefore, the arrays that receive the other spectral analysis results from the transform method arediscarded each time a new spectral analysis is performed.

Listing 12. Perform the spectral analysis.
magnitude1 = new double[len];real = new double[len];imag = new double[len];angle = new double[len];ForwardRealToComplex01.transform(data1,real, imag,angle,magnitude1,zeroTime,lowF,highF);magnitude2 = new double[len];real = new double[len];imag = new double[len];angle = new double[len];ForwardRealToComplex01.transform(data2,real, imag,angle,magnitude2,zeroTime,lowF,highF);magnitude3 = new double[len];real = new double[len];imag = new double[len];angle = new double[len];ForwardRealToComplex01.transform(data3,real, imag,angle,magnitude3,zeroTime,lowF,highF);magnitude4 = new double[len];real = new double[len];imag = new double[len];angle = new double[len];ForwardRealToComplex01.transform(data4,real, imag,angle,magnitude4,zeroTime,lowF,highF);magnitude5 = new double[len];real = new double[len];imag = new double[len];angle = new double[len];ForwardRealToComplex01.transform(data5,real, imag,angle,magnitude5,zeroTime,lowF,highF);}//end constructor

The spectral magnitude results

Note that the magnitude results are saved in the array objects referred to by magnitude1 , magnitude2 , etc. This will be important later when I discuss the interface methods defined by Dsp028 .

The end of the constructor

Listing 12 also signals the end of the constructor. When the constructor terminates, the object has been instantiated and populated with spectralanalysis results for five sinusoids using the parameters specified by the file named Dsp028.tx t.

The getparameters method

The getParameters method used in this program is the same as that used in Dsp029 , so I won't discuss it further.

The interface methods

The Dsp028 class must define the same six interface methods as the Dsp029 class, which I discussed earlier. The only difference in the interface methods is the identification of the array objectsfrom which the methods return data when the methods are called.

The code in Listing 13 is typical of the code for methods f1 through f5 . As you can see, these methods return the data stored in the magnitude arrays. These are the spectral analysis results that areplotted in Figure 9 , Figure 11 , and later in Figure 14 .

Listing 13. The method named f1.
public double f1(double x){ int index = (int)Math.round(x);if(index<0 || index>magnitude1.length-1){ return 0;}else{ return magnitude1[index]; }//end else}//end function

The program named Graph03

The plots in Figure 9 and Figure 11 were produced by entering the following at the command line prompt:

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
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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
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