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The program code

Image 2 shows a full-size view of the center panel in Image 1 . This panel contains the program code associated with the button.

Image 2. the center programming panel for relational01.

Missing image.
Image 2. The center programming panel for Relational01.

Initialize the variables

The top script in Image 2 initializes the values of all the variables to zero when the user clicks thegreen flag. You have seen code like this several times before in this series of modules, so I won't discuss it further.

When the button is clicked ...

Each of the bottom three scripts in Image 2 are executed when the user clicks the button in the Stage area in Image 1 . These three scripts are very similar. However, they use three different relational operators to compare the values of the left and right operands and they set the values inthree different output variables accordingly.

I will walk you through the construction of one of the scripts with a detailed explanation of each step in the process. You should be able toextend that explanation to the other two scripts.

An if-else block

I'm going to walk you through the process of creating one of the bottom three scripts shown in Image 2 .

Image 3 shows the result of

  • Selecting the button sprite in the lower-right panel of Image 1 .
  • Selecting Control in the upper-left panel.
  • Dragging the block labeled when button clicked into the center panel.
  • Dragging an if-else block from the lower-left panel into the center panel.
  • Connecting the if-else block to the block that is labeled when button clicked .
By the way, in case I forgot to tell you before, you can set the name of the sprite to button by clicking in the dark gray area in the upper-right of Image 3 and typing the name of the sprite.

Image 3. starting to use an if-else block.

Missing image.
Image 3. Starting to use an if-else block.

Need to put a conditional clause in the pocket

Note the depressed pocket immediately to the right of the word if on the if-else block. We must drop another block of the correct shape into this pocket. The code in that block must evaluate to either true orfalse.

If that code evaluates to true, the code that we will insert into the mouth of the block immediately below the word if will be executed.

If the code that we drop into the pocket evaluates to false, the code that we insert into the mouth of the block immediately below the word else will be executed.

Where are the blocks with the correct shape?

There are two buttons (possibly more) that we can click in the upper left in Image 3 that will expose blocks with shapes matching the pocket immediately to the right of the word if in Image 3 :

  • Sensing
  • Operators

We used a block having the correct shape from the Sensing group in the earlier module titled Scr0130: Sequence, Selection, and Loop . An image of the blocks exposed by the Sensing button is shown in Image 12 in that earlier module.

Will use blocks from the Operators group

In this module, we will use three of the blocks that are exposed by clicking the green Operators button as shown in Image 4 .

Image 4. green blocks exposed by clicking the operators button.

Missing image.
Image 4. Green blocks exposed by clicking the Operators button.

Questions & Answers

where we get a research paper on Nano chemistry....?
Maira Reply
what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
yes that's correct
I think
Nasa has use it in the 60's, copper as water purification in the moon travel.
nanocopper obvius
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
scanning tunneling microscope
how nano science is used for hydrophobicity
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
what is differents between GO and RGO?
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
analytical skills graphene is prepared to kill any type viruses .
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
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.
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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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