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Doesn't know and doesn't care

The plotting program doesn't know, and doesn't care how the interface method decides on the value to return for each value that it receives as an incomingparameter. The plotting program simply calls the methods to get the data, and then plots the returned values.

Computed "on the fly"

For example, the returned values could be computed and returned "on the fly," as was the case in the example program named Graph01Demo , which I explained in the module titled Plotting Engineering and Scientific Data using Java .

Returned from an array

On the other hand, the values could have been computed earlier and saved in an array. That is the case with all the programs that I will explain in thismodule.

From a disk file, a database, the internet, etc.

The returned values could be read from a disk file, obtained from a databaseon another computer, or obtained from any other source such as another computer on the Internet.

All that matters is that when the plotting program calls one of the five methods named f1 through f5 , passing a double value as a parameter, it expects to receive a double value in return, and it will plot the value that it receives.

The getNmbr method

The getNmbr method for the class named Dsp029 is shown in Listing 6 .

Listing 6. The getNmbr method.
public int getNmbr(){ //Return number of functions to// process. Must not exceed 5. return numberSinusoids;}//end getNmbr

This is a very simple method. It returns the value stored in the variable named numberSinusoids . This variable may contain the default value established by Listing 1 , or may contain the value read from the file named Dsp029.txt by the method named getParameters .

The method named f1

The code for the method named f1 is shown in Listing 7 .

Listing 7. The method named f1.
public double f1(double x){ int index = (int)Math.round(x);if(index<0 || index>data1.length-1){ return 0;}else{ return data1[index]; }//end else}//end function

Note that there is not a one-to-one correspondence between horizontal coordinate values and pixels on the screen. For example, it may sometimes benecessary to plot 90 values across an area of the screen containing 110 pixels. The plotting program must interpolate properly to deal with that issue.Therefore, the plotting program deals with horizontal coordinates as type double and then converts those coordinate values to integer pixel values when the timecomes to actually draw the material on the screen.

Round from double to int

The method named f1 receives an incoming horizontal coordinate value as type double . It rounds that value to the nearest value of type long and casts it to type int to determine the index value to use when retrieving the corresponding verticalvalue from the array object.

If the index value is outside the bounds of the array, the method simply returns a value of zero. Otherwise, it uses the index value to return the valuestored in the array object at that index.

The remaining interface methods

The remaining four interface methods are identical to the method named f1 , except that each method returns data values stored in a different array object. Therefore, I won't discuss those methods.

Questions & Answers

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
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
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.
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.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
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.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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