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Specifying the values

After dragging a programming block from the Variables area into the programming area, you can:

  • 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 area at the right end ofthe block, or
  • Drag some other block and drop it into the white or gray area.

In some cases, the area looks white and in other cases it looks gray. I will refer to it as the white area in both cases.

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

  1. A horizontal rectangle with rounded corners such as the orange block labeled Counter in Image 2 . (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 6 . (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 areas with rounded corners of the programming blocks in Image 2 .

Blocks having the pointed ends are eligible for being dropped into the darker orange areas having a similar shape on the blocks near the bottom of Image 4 .

Either shape of block is eligible for being dropped into the white areas with square corners shown in Image 2 . Thus the block in Image 2 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 2 labeled Counter and counter are eligible for being dropped into the white areas of the two programming blocks shown in Image 2 . 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 2 (see Image 6 ) you will expose several different blocks with rounded corners that are eligible for being dropped into thewhite areas in Image 2 according to the rules described above.

Cause the variables to be displayed

Checking the boxes to the left of the variable names in Image 2 causes them to be displayed in the upper-left corner of the large white Stage area 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 2 . When you click that button, the dialog shown in Image 3 appears on the screen asking you to provide the name for the new variable.

Image 3. dialog for entering a variable name.

Missing image
Image 3. 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.

Allowable variable names and lengths

Most programming languages have very specific requirements regarding the allowable characters for variable names. I suspect that this is also true ofScratch, but I haven't found that specification anywhere. You will probably be okay as long as you stick with letters, numbers, the underscore character"_", and the hyphen or minus sign "-".

Questions & Answers

can someone help me with some logarithmic and exponential equations.
Jeffrey Reply
sure. what is your question?
okay, so you have 6 raised to the power of 2. what is that part of your answer
I don't understand what the A with approx sign and the boxed x mean
it think it's written 20/(X-6)^2 so it's 20 divided by X-6 squared
I'm not sure why it wrote it the other way
I got X =-6
ok. so take the square root of both sides, now you have plus or minus the square root of 20= x-6
oops. ignore that.
so you not have an equal sign anywhere in the original equation?
Commplementary angles
Idrissa Reply
im all ears I need to learn
right! what he said ⤴⤴⤴
what is a good calculator for all algebra; would a Casio fx 260 work with all algebra equations? please name the cheapest, thanks.
Kevin Reply
a perfect square v²+2v+_
Dearan Reply
kkk nice
Abdirahman Reply
algebra 2 Inequalities:If equation 2 = 0 it is an open set?
Kim Reply
or infinite solutions?
The answer is neither. The function, 2 = 0 cannot exist. Hence, the function is undefined.
Embra Reply
if |A| not equal to 0 and order of A is n prove that adj (adj A = |A|
Nancy Reply
rolling four fair dice and getting an even number an all four dice
ramon Reply
Kristine 2*2*2=8
Bridget Reply
Differences Between Laspeyres and Paasche Indices
Emedobi Reply
No. 7x -4y is simplified from 4x + (3y + 3x) -7y
Mary Reply
is it 3×y ?
Joan Reply
J, combine like terms 7x-4y
Bridget Reply
im not good at math so would this help me
Rachael Reply
I'm not good at math so would you help me
what is the problem that i will help you to self with?
how do you translate this in Algebraic Expressions
linda Reply
Need to simplify the expresin. 3/7 (x+y)-1/7 (x-1)=
Crystal Reply
. After 3 months on a diet, Lisa had lost 12% of her original weight. She lost 21 pounds. What was Lisa's original weight?
Chris 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
what is the k.e before it land
what is the function of carbon nanotubes?
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
can nanotechnology change the direction of the face of the world
Prasenjit Reply
At high concentrations (>0.01 M), the relation between absorptivity coefficient and absorbance is no longer linear. This is due to the electrostatic interactions between the quantum dots in close proximity. If the concentration of the solution is high, another effect that is seen is the scattering of light from the large number of quantum dots. This assumption only works at low concentrations of the analyte. Presence of stray light.
Ali Reply
the Beer law works very well for dilute solutions but fails for very high concentrations. why?
bamidele Reply
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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