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The body of the method named f4 is similar to the body of the method named f3 , except that f4 computes and returns sine values instead of cosine values. Also, the value of x is used differently so that the period of the curve produced by f4 is twice the period of the curve produced by f3 .

The method named f5

Finally, the bottom white plotting area in Figure 1 shows the output produced by the method named f5 , which is shown in Listing 8 .

Listing 8. The method named f5.
public double f5(double x){ return 100*(Math.sin(x/20.0)*Math.cos(x/10.0));}//end f5

This method computes and returns the product of sine and cosine functions identical to those discussed above.

The end of the class definition

Listing 8 also shows the closing curly brace that signifies the end of the class definition for the class named Graph01Demo .

That's really all that you need to know to be able to make effective use of the generalized plotting program named Graph01 . If you can define the methods named f1 through f5 , which will return the required values for your computational experiment, then you canmake use of this program to plot your data.

The class named Dsp002

Lest you go away believing that this is all too trivial to be interesting, I am going to show you another example that is far from trivial. In the nextexample, I will demonstrate two of the most important operations in the field commonly referred to as digital signal processing, or DSP for short.

Because many of you are unlikely to be familiar with the techniques and terminology involved, the discussion will of necessity be fairly shallow.However, I do want to show at least one example of how you can perform substantive computational experiments using this approach.

A DSP example

A DSP example involving convolution filtering and spectral analysis is shown in Figure 3 .

Figure 3. A Digital Signal Processing (DSP) Example.
missing image

In the field of DSP, the five individual plots shown in the plotting areas of Figure 3 are commonly referred to as traces. I will use that terminology in this discussion.

White random noise

The top trace in the area with the white background shows about 256 samples of white random noise. When we get to the code, we will see that this data wascreated using a Java pseudo-random number generator.

A convolution filter

The second trace from the top shows a 33-point narrow-band convolution filter, which is simply a chunk taken out of a sinusoid whose frequency isone-fourth the sampling frequency. In other words, the sinusoid is represented by four samples per cycle.

The convolution filter output

The middle trace shows the result of applying the narrow-band convolution filter to the white noise. The output from the convolution process was amplifiedto bring it back into an appropriate amplitude range for visual analysis.

If you compare the middle trace with the top trace, you will notice that much of the high-frequency energy and much of the low-frequency energy has beenremoved. Most of the energy in the middle trace appears to be about the same frequency as the design frequency of the convolution filter (which is what we would expect) .

Questions & Answers

how did you get 1640
Noor Reply
If auger is pair are the roots of equation x2+5x-3=0
Peter Reply
Wayne and Dennis like to ride the bike path from Riverside Park to the beach. Dennis’s speed is seven miles per hour faster than Wayne’s speed, so it takes Wayne 2 hours to ride to the beach while it takes Dennis 1.5 hours for the ride. Find the speed of both bikers.
MATTHEW Reply
420
Sharon
from theory: distance [miles] = speed [mph] × time [hours] info #1 speed_Dennis × 1.5 = speed_Wayne × 2 => speed_Wayne = 0.75 × speed_Dennis (i) info #2 speed_Dennis = speed_Wayne + 7 [mph] (ii) use (i) in (ii) => [...] speed_Dennis = 28 mph speed_Wayne = 21 mph
George
Let W be Wayne's speed in miles per hour and D be Dennis's speed in miles per hour. We know that W + 7 = D and W * 2 = D * 1.5. Substituting the first equation into the second: W * 2 = (W + 7) * 1.5 W * 2 = W * 1.5 + 7 * 1.5 0.5 * W = 7 * 1.5 W = 7 * 3 or 21 W is 21 D = W + 7 D = 21 + 7 D = 28
Salma
Devon is 32 32​​ years older than his son, Milan. The sum of both their ages is 54 54​. Using the variables d d​ and m m​ to represent the ages of Devon and Milan, respectively, write a system of equations to describe this situation. Enter the equations below, separated by a comma.
Aaron Reply
find product (-6m+6) ( 3m²+4m-3)
SIMRAN Reply
-42m²+60m-18
Salma
what is the solution
bill
how did you arrive at this answer?
bill
-24m+3+3mÁ^2
Susan
i really want to learn
Amira
I only got 42 the rest i don't know how to solve it. Please i need help from anyone to help me improve my solving mathematics please
Amira
Hw did u arrive to this answer.
Aphelele
hi
Bajemah
-6m(3mA²+4m-3)+6(3mA²+4m-3) =-18m²A²-24m²+18m+18mA²+24m-18 Rearrange like items -18m²A²-24m²+42m+18A²-18
Salma
complete the table of valuesfor each given equatio then graph. 1.x+2y=3
Jovelyn Reply
x=3-2y
Salma
y=x+3/2
Salma
Hi
Enock
given that (7x-5):(2+4x)=8:7find the value of x
Nandala
3x-12y=18
Kelvin
please why isn't that the 0is in ten thousand place
Grace Reply
please why is it that the 0is in the place of ten thousand
Grace
Send the example to me here and let me see
Stephen
A meditation garden is in the shape of a right triangle, with one leg 7 feet. The length of the hypotenuse is one more than the length of one of the other legs. Find the lengths of the hypotenuse and the other leg
Marry Reply
how far
Abubakar
cool u
Enock
state in which quadrant or on which axis each of the following angles given measure. in standard position would lie 89°
Abegail Reply
hello
BenJay
hi
Method
I am eliacin, I need your help in maths
Rood
how can I help
Sir
hmm can we speak here?
Amoon
however, may I ask you some questions about Algarba?
Amoon
hi
Enock
what the last part of the problem mean?
Roger
The Jones family took a 15 mile canoe ride down the Indian River in three hours. After lunch, the return trip back up the river took five hours. Find the rate, in mph, of the canoe in still water and the rate of the current.
cameron Reply
Shakir works at a computer store. His weekly pay will be either a fixed amount, $925, or $500 plus 12% of his total sales. How much should his total sales be for his variable pay option to exceed the fixed amount of $925.
mahnoor Reply
I'm guessing, but it's somewhere around $4335.00 I think
Lewis
12% of sales will need to exceed 925 - 500, or 425 to exceed fixed amount option. What amount of sales does that equal? 425 ÷ (12÷100) = 3541.67. So the answer is sales greater than 3541.67. Check: Sales = 3542 Commission 12%=425.04 Pay = 500 + 425.04 = 925.04. 925.04 > 925.00
Munster
difference between rational and irrational numbers
Arundhati Reply
When traveling to Great Britain, Bethany exchanged $602 US dollars into £515 British pounds. How many pounds did she receive for each US dollar?
Jakoiya Reply
how to reduced echelon form
Solomon Reply
Jazmine trained for 3 hours on Saturday. She ran 8 miles and then biked 24 miles. Her biking speed is 4 mph faster than her running speed. What is her running speed?
Zack Reply
d=r×t the equation would be 8/r+24/r+4=3 worked out
Sheirtina
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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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