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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

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
Do somebody tell me a best nano engineering book for beginners?
s. Reply
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
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?
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
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what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
many many of nanotubes
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I'm interested in nanotube
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
preparation of nanomaterial
Victor Reply
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
Himanshu Reply
good afternoon madam
what is system testing
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
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
silver nanoparticles could handle the job?
not now but maybe in future only AgNP maybe any other nanomaterials
I'm interested in Nanotube
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
can nanotechnology change the direction of the face of the world
Prasenjit Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
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