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A cosine

The program named Cosine01 shown in Listing 20 produces the graphic output shown in Figure 12 .

Figure 12. Graphic output from the program named Cosine01.

Missing image

The only significant difference between this program and the program named Parabola01 is the method named function shown in Listing 14 .

Listing 14 . The method named function for Cosine01. double function(double xVal){ double yVal = Math.cos(2*Math.PI*xVal);return yVal; }//end function

This method evaluates and returns the y-value for each incoming x-value for a cosine function with no offset centered at the origin.

y = cos(2*pi*x)

Figure 12 shows two cycles of the cosine curve, which is periodic. When viewing Figure 12 , keep in mind that positive values go down the page. Thus the positive peak of the cosine function at the origin points down.

As in the previous section, that is probably all that needs to be said about the program named Cosine01 .

Run the programs

I encourage you to copy the code from Listing 15 through Listing 20 . Execute the code and confirm that you get the same results as those shown in in this lesson. Experiment with the code,making changes, and observing the results of your changes. Make certain that you can explain why your changes behave as they do.

Complete program listings

Complete listings of the programs discussed in this lesson are provided in Listing 15 through Listing 20 below.

Listing 15 . The program named Line01. /*File Line01 Copyright 2016 R.G.Baldwin ********************************************************************/import java.awt.Color; public class Line01{//Driver classpublic static void main(String[] args){Line01Runner obj = new Line01Runner(); obj.run();}//end main }//end class Line01//=================================================================// class Line01Runner{//Instantiate the World and Turtle objects. private World world = new World(300,300);private Turtle turtle = new Turtle(0,0,world); //---------------------------------------------------------------//public void run(){ //Make the turtle invisibleturtle.hide();//Prepare the pen turtle.setPenColor(Color.RED);turtle.setPenWidth(2);//Draw the axes in RED turtle.penUp();turtle.moveTo(world.getWidth()/2,0); turtle.penDown();turtle.moveTo(world.getWidth()/2,world.getHeight()); turtle.penUp();turtle.moveTo(world.getWidth(),world.getHeight()/2); turtle.penDown();turtle.moveTo(0,world.getHeight()/2); turtle.penUp();turtle.moveTo(0,0); //Prepare the scale factorsdouble xScale = 1.0*world.getWidth()/2; double yScale = 1.0*world.getHeight()/2;//Draw a line in BLUE. turtle.setPenColor(Color.BLUE);double slope = 1.0; double yIntercept = 0.0;drawLine(xScale,yScale,slope,yIntercept); //Draw another line in GREEN.turtle.penUp(); turtle.setPenColor(Color.GREEN);slope = -0.5; yIntercept = 0.5;drawLine(xScale,yScale,slope,yIntercept);//Draw another line in BLACK. turtle.penUp();turtle.setPenColor(Color.BLACK); slope = 2.0;yIntercept = -0.5; drawLine(xScale,yScale,slope,yIntercept);}//end run method //---------------------------------------------------------------////Method to draw a line given several incoming parameters that// describe the line and the plotting parameters. void drawLine(double xScale,double yScale,double slope,double yIntercept){ double yVal = 0;int row = 0; int col = 0;double xVal = -1.0;for(int cnt=0; cnt<=100;cnt++,xVal += 0.02){ //Get a y-value for a given x-value.yVal = function(xVal,slope,yIntercept);//Scale the x and y values to match the plotting surface col = (int)(xVal*xScale);row = (int)(yVal*yScale); //Move to the first point without drawing a line because the// pen is not down. Translate the origin to the center in the // process.turtle.moveTo(col + world.getWidth()/2, row + world.getHeight()/2);//Lower the pen in order to draw a line from each point to the// next point. turtle.penDown();}//end for loop }//end drawLine method//---------------------------------------------------------------////This method evaluates and returns the y-value for each x-value// for a line described by the equation // y = slope*x + yInterceptdouble function(double xVar,double slope,double yIntercept){ double yVar = (yIntercept) + (slope*xVar);return yVar; }//end function//---------------------------------------------------------------//}//end class Line01Runner

Questions & Answers

anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
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.
Bharti
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
Daniel
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
Maciej
characteristics of micro business
Abigail
for teaching engĺish at school how nano technology help us
Anassong
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
NANO
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
s.
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.
Tarell
what is the actual application of fullerenes nowadays?
Damian
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.
Tarell
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.
Virgil
is Bucky paper clear?
CYNTHIA
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
NANO
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.
Harper
Do you know which machine is used to that process?
s.
how to fabricate graphene ink ?
SUYASH Reply
for screen printed electrodes ?
SUYASH
What is lattice structure?
s. Reply
of graphene you mean?
Ebrahim
or in general
Ebrahim
in general
s.
Graphene has a hexagonal structure
tahir
On having this app for quite a bit time, Haven't realised there's a chat room in it.
Cied
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
China
Cied
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
Porter
many many of nanotubes
Porter
what is the k.e before it land
Yasmin
what is the function of carbon nanotubes?
Cesar
I'm interested in nanotube
Uday
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
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Source:  OpenStax, Object-oriented programming (oop) with java. OpenStax CNX. Jun 29, 2016 Download for free at https://legacy.cnx.org/content/col11441/1.201
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