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  • Identify the variable to which that block applies by selecting the variable name in the pull-down list built into the block.
  • Enter a literal numeric or string value from the keyboard into the white or gray text field at the right end ofthe block, or
  • Drag some other block and drop it into the white or gray text field.

There are at least two different shapes that are eligible for being dropped into such text fields:

  1. A horizontal rectangle with rounded corners such as the orange block labeled Counter in Image 1 . (This shape seems to always be associated with a numeric or string value.)
  2. A horizontal rectangle with pointed ends as shown by several of the blocks in Image 4 . (This shape seems to always be associated with a boolean result of true or false.)

Blocks having the rounded corners are eligible for being dropped into the white text fields with rounded corners of the programming blocks in Image 1 .

Blocks having the pointed ends are eligible for being dropped into the darker orange text fields having a similar shape on the blocks that areexposed by clicking the Control button in the programming interface.

Either shape of block is eligible for being dropped into the white text fields withsquare corners shown in Image 1 . Thus the block in Image 1 that is used to set a variable to a value can set the value to a numeric value,a string value, or a boolean value.

(Note that the two variable blocks shown in Image 1 labeled Counter and counter are eligible for being dropped into the white text fields ofthe two programming blocks shown in Image 1 . This makes it possible to cause the value of one variable to depend on the valueof another variable.)

If you click the Operators button shown in Image 1 (see Image 4 ) you will expose several different blocks with rounded corners that are eligible for being dropped into thewhite text fields in Image 1 according to the rules described above.

Cause the variables to be displayed

As mentioned earlier, checking the boxes to the left of the variable names in Image 1 causes them to be displayed in the upper-left corner of the Stage shown in Image 1 . (Clicking the show and hide blocks will also check and uncheck the checkboxes, which in turn will show or hide the variables on the stage.)

Create a new variable

You create a new variable by clicking the button labeled Make a variable shown in Image 1 . When you click that button, the dialogshown in Image 2 appears on the screen asking you to provide the name for the new variable.

Image 2. dialog for entering a variable name.

Missing image
Image 2. Dialog for entering a variable name.

At that point, you simply type in the name for the new variable and click the OK button.

The radio buttons on that dialog allow you to specify which sprites have access to the variable.

The disabled cloud variable button (shown in light gray in Image 2 ) is a new feature of Scratch 2.0. Apparently registered users who are signed in can check that button and save the variable on the MITwebsite or on a website controlled by MIT. I wasn't signed in, which is why it was disabled.

Questions & Answers

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.
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
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.
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
How can I make nanorobot?
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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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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