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Figure 5. Program output for Line01 for a 400x150 world.

Missing image

Draw the BLUE line

The code in Listing 3 initializes several variables and then calls a method named drawLine to implement the steps listed above to draw the BLUE line shown in Figure 3 .

Listing 3 . Draw the BLUE line. double 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);

The method named drawLine

Once again, I will put the run method on hold while we examine the code that actually draws the line as shown in Listing 4 .

Listing 4 . The method named drawLine. 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

If you examine the code in Listing 4 along with values assigned to the variables in Listing 3 , you should be able to see the correlation between the code and the steps given earlier . In particular, you should be able to see how this code produces the BLUE lineshown in Figure 3 .

Note that the code in Listing 4 calls the method named function (shown in Listing 2 ) to get the values that define the line for the given slope and the given y-intercept value.

Repeat the process to draw two more lines

Returning to the run method, the code in Listing 5 repeats the process twice to draw the GREEN line and the BLACK line shown in Figure 3 for different slope and y-intercept values.

Listing 5 . Repeat the process to draw two more lines. //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

Listing 5 also signals the end of the run method and the end of the program.

A parabola

The program named Parabola01 shown in Listing 16 produces the graphic output shown in Figure 6 .

Figure 6. Graphic output from the program named Parabola01.

Missing image

The method named function for Parabola01

The method named function for the program named Parabola01 is shown in Listing 6 .

This method evaluates and returns the y-value for each incoming x-value for a parabola with no offsets centered at the origin as defined by the following equation:

Questions & Answers

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.
what is biological synthesis of nanoparticles
Sanket Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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