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A reference to the populated Hashtable object referred to by piano is returned when the for loop terminates at the bottom of Listing 18 .

Listing 18 also signals the end of the getPiano method and the end of the class named PlayerPiano01 . However, we aren't finished yet. We need to go back and examine the code in the method named makeMusic that we put on the back burner a little earlier.

Beginning of the method named makeMusic

The method named makeMusic begins in Listing 19 . This method transforms the notes for a clef into an array of amplitude values. This method doesn't know the difference between a treble clef and a bass clef.It is called once to transform the treble clef at the bottom of Listing 12 . It is called again to transform the bass clef in Listing 13 if the user provides a text file containing bass clef data.

Listing 19 . Beginning of the method named makeMusic.
void makeMusic(ArrayList clef,int beatsPerSec){ double gain = 4000.0;//Set the output volume to a reasonable level.//Get a hashtable that maps note names into note frequencies from A2 // through A7. Note that the name "X" is used to indicate a period of// silence or a rest, so it is appended onto the end of the hashtable with // a frequency of 0.0.//Frequency values can be checked against // http://www.phy.mtu.edu/~suits/notefreqs.html.Hashtable piano = getPiano(); piano.put("X",0.0);//Miscellaneous variables double freq = 0;int beats = 0; double scaleFactor = 0;

Nothing in Listing 19 should require an explanation beyond the embedded comments.

Process each array containing duration and note names in the ArrayList object

Listing 20 shows the beginning of a while loop that uses an iterator to process each array containing duration and note names in the ArrayList object

Listing 20 . Process each array containing duration and note names in the ArrayList object.
Iterator iter = clef.iterator(); while(iter.hasNext()){//Get the next array containing duration and note names String[]array = (String[])iter.next();//Get the duration of the note in beats beats = Integer.parseInt(array[0]);

The code in Listing 20 accesses the next array and then extracts the duration (in beats) from the array and stores it in the variable named beats .

Process each sample

Listing 21 shows the beginning of a for loop that is used to process each sample that makes up this note. The output sampling rate is constant. Therefore,notes with a short duration comprise fewer samples than notes with a long duration.

Listing 21 . Process each sample.
for(int cnt = 0; cnt<beats*audioParams.sampleRate/beatsPerSec; cnt++){ //Compute the time for this iteration to use when evaluating the// cosine function. double time = cnt/audioParams.sampleRate;double sum = 0;//sum of values for this iteration

Process each piano key that is pressed

Recall that a human piano player can press several keys simultaneous, as in (9,A3,C4,E4) at the end of Listing 30 . In this case, the piano player would press threekeys simultaneously on the piano keyboard and hold them down for nine beats.

Questions & Answers

How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
scanning tunneling microscope
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.
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
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