# 3.4 Java3003: drawing graphs with turtles and pixels  (Page 6/13)

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`y = x*x`
Listing 6 . The method named function for Parabola01. ```double function(double xVal){ double yVal = xVal*xVal;return yVal; }//end function```

A plot of the output of the method named function would look like the curve shown in Figure 7 with no offsets if the x and y scaling values were set to one-half the width and height of the world respectively.

Figure 7. Parabola with zero offsets.

It will be instructive to see how this program uses offsets and scaling values to transform the image shown in Figure 7 into the image shown in Figure 6 .

## Drawing parameters for Parabola01

The code fragment shown in Listing 7 shows the drawing parameters that were used to produce the output shown in Figure 6 .

Listing 7 . Drawing parameters for Parabola01. ```double xOff = 0.25;//offset relative to 1.0 double yOff = -0.25;double xScale = 0.75*world.getWidth()/2; double yScale = 1.25*world.getHeight()/2;```

## Drawing parameters with zero offsets

The parameters that were used to produce the output shown in Figure 7 are shown below:

```double xOff = 0.0;//offset relative to 1.0 double yOff = -0.0;double xScale = 1.0*world.getWidth()/2; double yScale = 1.0*world.getHeight()/2;```

Note in particular that the offsets given by xOff and yOff are set to zero and the scale factors given by xScale and yScale are one-half the width and height of the world respectively.

## Changing the offset values

Increasing the offsets for xOff and yOff to 0.25 and -0.25 respectively as shown in Figure 7 and making no other changes produces the output shown in Figure 8

Figure 8. A parabola with offsets.

In comparison with Figure 7 , changing the value of xOff to 0.25 caused the peak to move to the right (positive direction) one-fourth of the way from the center origin to the right edge of the world. (That change also caused a portion of the curve to fall outside the right boundary of the world.)

Similarly, changing the value of yOff to -0.25 caused the peak to move up (negative direction) one-fourth of the way from the center origin to the top edge of the world.

## Changing the scale factors

Following that, changing the values of xScale and yScale to the values shown in Listing 7 produces the graphic output shown in Figure 6 . The change in xScale decreased the total width of the curve and prevented it from exceeding the rightmost boundary of theworld. The change in yScale increased the overall height of the curve causing it to almost touch the lower boundary of the world.

## Draw the parabolic function in BLUE

The code in Listing 8 draws the blue parabolic function shown in Figure 6 .

Listing 8 . Draw the parabolic function in BLUE. ```double yVal = 0; int row = 0;int col = 0; double xVal = -1;turtle.setPenColor(Color.BLUE); for(int cnt=0; cnt<=100;cnt++,xVal += 0.02){ //Get a y-value for the given x-value.yVal = function(xVal); //Apply the offsets and scale the resultscol = (int)((xOff+xVal)*xScale); row = (int)((yOff+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 run method```

where we get a research paper on Nano chemistry....?
what are the products of Nano chemistry?
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
learn
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
learn
da
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Bhagvanji
Preparation and Applications of Nanomaterial for Drug Delivery
revolt
da
Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
I only see partial conversation and what's the question here!
what about nanotechnology for water purification
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
Damian
yes that's correct
Professor
I think
Professor
Nasa has use it in the 60's, copper as water purification in the moon travel.
Alexandre
nanocopper obvius
Alexandre
what is the stm
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
Rafiq
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
Hafiz
what is Nano technology ?
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
why we need to study biomolecules, molecular biology in nanotechnology?
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
why?
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
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