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The program named ForLoop02

This program is an upgrade of the program named ForLoop01 . The behavior of this program is the same as the earlier program with the followingexceptions:

  • A slider variable named numberLoops is placed in the upper left corner of the Stage as shown in Image H .
  • When the user clicks the green flag, orthogonal axes are drawn through the origin of the Stage and the cat is placed at the origin.
  • When the user clicks the cat, the number of times the code in the repeat block is executed is determined by the current value of the slider variable.
  • As the code in the repeat block is repetitively executed, the path of the cat is traced out on the Stage as a series of short straightline segments, producing the circular path shown in Image I .

Image h. program forloop02 output after clicking the green flag.

Missing image.
Image H. Program ForLoop02 output after clicking the green flag.

Image i. program forloop02 output after clicking the cat.

Missing image.
Image I. Program ForLoop02 output after clicking the cat.

The program code

The code for this program is shown in Image J .

Image j. program code for the program named forloop02.

Missing image.
Image J. Program code for the program named ForLoop02.

Create a variable

The code in the left panel in Image J creates a variable with a slider named numberLoops and causes it to be displayed on the Stage as shown in Image I .

The initialization code

Although there is quite a lot of code that is executed when the green flag is clicked, there is nothing new there. All of that code has been explained in thisor earlier modules. For review, the green pen blocks and the blue go to blocks are used together to draw the Cartesian coordinates. Note that the pen is down when the initialization code finishes executing. As a result, a line willbe drawn whenever the cat sprite moves.

The repeat block

The only thing that is really new to this program is the use of the variable block named numberLoops to specify the number of times that the code in the repeat block will be executed each time the cat is clicked. Otherwise the code in the repeat block in Image J is the same as the code in the repeat block shown in Image F .

The operational difference

The operational difference is that each time the repeat block in Image F is executed, the code inside the repeat block will be executed 24 times. Each time the repeat block in Image J is executed, the number of times that the code inside the repeat block will be executed is specified by thecurrent position of the slider in Image I . This, in effect converts the static program named ForLoop01 into an interactive program in which the user has some control over the program behavior at runtime.

As mentioned earlier, because the pen is down, a line is drawn each time the cat sprite moves. That is what draws the circular path shown in Image I .

Online versions of these programs are available

Copies of these two programs have been posted online for your review (see Resources for the URL) . If you don't find the programs using that URL, search the Scratch site for the usernamed dbal.

Questions & Answers

what is the stm
Brian Reply
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?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
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
what is Nano technology ?
Bob Reply
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?
Damian Reply
what king of growth are you checking .?
Renato
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
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
sciencedirect big data base
Ernesto
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
How can I make nanorobot?
Lily
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
how can I make nanorobot?
Lily
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
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Source:  OpenStax, Teaching beginners to code. OpenStax CNX. May 27, 2013 Download for free at http://cnx.org/content/col11498/1.20
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