### Spotlight: The Operators

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## The operators manipulate data.

You will notice that the blocks have different shapes.  Subsequently, some fit together into some blocks but not others.  Test it out and find out which blocks fit together

The first four perform basic maths operations: add, subtract, multiply and divide where divide will give a decimal (the numbers entered in are floating point such as 6.0).

Remember the order of operations matters; furthermore, the rounded blocks will act as parentheses, so anything to be calculated first is anything in parenthesis.

Example:
(2+3+4) x5 = 45
2+3+ 4 x5 = 25

The next block will pick a random number between any two numbers that you enter.

### The inequality and equals signs

> Greater than, for example 45 > 20

= Equal, for example 3 = 3

### The Boolean operators (named after George Boole) Boolean operators have two values true or false

And both must be true.
Or Either one or both must be true.
Not this gives a false answer when true.

Truth table

### Join, letter_of _ and length_of_

Join
Join is another word for concatenation (this term is used a lot in programming). The block will join things together.
For example

Letter_of_
This will pick out that letter in the sequence, so if you want to pick out n in concatenation you would use Letter 3 of concatenation.

Length of_
A string is a sequence of characters.  This block will find the number of characters of the string and output that value.

### Mod and Round

Mod
This handy little operator will return the remainder of division.  If you enter 8 mod 2 the return is 0 because there is no remainder. On the other hand, if you enter 7 mod 2 the return is 1.

Round
This will round decimals to the nearest integer.  Integers are whole numbers like 1, 45 and 134.  However, numbers like 5.5 or 2/3 are not.

Example, if you enter 3.45, the return will be 3 or if you enter 5.5, the return will be 6

_of_
This computes a function.  You can use the drop down menu by clicking on the black arrow and choose from a list

This computes a function.  You can use the drop down menu by clicking on the black arrow, then choose from a list

The options are:

abs  = absolute value
sqrt = square root
sin   = sine
cos  = cosine
tan  = tangent
asin = arcsine (inverse of sine or sin^-1)
acos = arccosine (inverse of cosine or sin^-1)
atan = arctan (inverse or tan^-1)
ln    = Natural log
log   = logarithm
e^   = Euler's number to the power of something
10^ = 10 to the power of something

Note: The online version has two extra
floor     = no number lower than
Ceiling  = no number higher than

Key points
• The operator blocks manipulate numbers
• Count characters in a string - this could be letters, numbers or even symbols
• Can pick out a letter, value or symbol in a string.

Happy coding :-)
Next Spotlight: The control blocks