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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 do they get the third part x = (32)5/4
kinnecy Reply
can someone help me with some logarithmic and exponential equations.
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sure. what is your question?
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I don't understand what the A with approx sign and the boxed x mean
it think it's written 20/(X-6)^2 so it's 20 divided by X-6 squared
I'm not sure why it wrote it the other way
I got X =-6
ok. so take the square root of both sides, now you have plus or minus the square root of 20= x-6
oops. ignore that.
so you not have an equal sign anywhere in the original equation?
Commplementary angles
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algebra 2 Inequalities:If equation 2 = 0 it is an open set?
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or infinite solutions?
The answer is neither. The function, 2 = 0 cannot exist. Hence, the function is undefined.
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Kristine 2*2*2=8
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Differences Between Laspeyres and Paasche Indices
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No. 7x -4y is simplified from 4x + (3y + 3x) -7y
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. After 3 months on a diet, Lisa had lost 12% of her original weight. She lost 21 pounds. What was Lisa's original weight?
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Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
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what is the application of nanotechnology?
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
anybody can imagine what will be happen after 100 years from now in nano tech world
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
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silver nanoparticles could handle the job?
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Prasenjit Reply
At high concentrations (>0.01 M), the relation between absorptivity coefficient and absorbance is no longer linear. This is due to the electrostatic interactions between the quantum dots in close proximity. If the concentration of the solution is high, another effect that is seen is the scattering of light from the large number of quantum dots. This assumption only works at low concentrations of the analyte. Presence of stray light.
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the Beer law works very well for dilute solutions but fails for very high concentrations. why?
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Source:  OpenStax, Accessible objected-oriented programming concepts for blind students using java. OpenStax CNX. Sep 01, 2014 Download for free at https://legacy.cnx.org/content/col11349/1.17
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