Operators

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Exclamation.png Warning!!!!

Operators are very important. The way the IB wants you to use operators is different than the way you will use them in real life.


Programming basics[1]

An operator is something that takes one or more values (or expressions, in programming jargon) and yields another value (so that the construction itself becomes an expression)[2].

There are many different types of operators, but the ones we primarily concern ourselves with are boldfaced below. If you'd like to learn more about different types of operators in PHP, please click here.

  • Operator Precedence
  • Arithmetic Operators
  • Assignment Operators
  • Bitwise Operators
  • Comparison Operators
  • Error Control Operators
  • Execution Operators
  • Incrementing/Decrementing Operators
  • Logical Operators
  • String Operators
  • Array Operators
  • Type Operators

Python operators cheatsheet

Click here for an excellent python cheatsheet

Arithmetic operators

An example of some arithmetic operators in PHP can be found below [3].

Example Name Result
+$a Identity Conversion of $a to int or float as appropriate.
-$a Negation Opposite of $a.
$a + $b Addition Sum of $a and $b.
$a - $b Subtraction Difference of $a and $b.
$a * $b Multiplication Product of $a and $b.
$a / $b Division Quotient of $a and $b.
$a % $b Modulus Remainder of $a divided by $b.
$a ** $b Exponentiation Result of raising $a to the $b'th power.

Conditional operators

An example of some conditional operators in PHP can be found below [4].

Example Name Result
$a == $b Equal TRUE if $a is equal to $b after type juggling.
$a === $b Identical TRUE if $a is equal to $b, and they are of the same type.
$a != $b Not equal TRUE if $a is not equal to $b after type juggling..
$a <> $b Not equal TRUE if $a is not equal to $b after type juggling.
$a !== $b Not identical TRUE if $a is not equal to $b, or they are not of the same type.
$a < $b Less than TRUE if $a is strictly less than $b.
$a > $b Greater than TRUE if $a is strictly greater than $b.
$a <= $b Less than or equal to TRUE if $a is less than or equal to $b.
$a >= $b Greater than or equal to TRUE if $a is greater than or equal to $b.
$a <=> $b Spaceship An integerA natural number, a negative of a natural number, or zero. less than, equal to, or greater than zero when $a is respectively less than, equal to, or greater than $b. Available as of PHP 7.

A video

This video references the C programming language and scratch, but the ideas about operators are excellent. In the case of conditionals, PHP and C share similar syntax (but not exact).

The way the IB wants you to use operators

Please know all code submitted to the IB (with the exceptionanomalous or exceptional conditions requiring special processing – often changing the normal flow of program execution of object oriented programming) is in pseudocode. The way we write operators in pseudocode is different than the way we might write them in the real world.

Click here to view a file describing approved notation, including pseudocode This is the approved notation sheet from the IB.

Below is a graphic that is taken from the above PDF file to help you understand how the IB wants operators to look.

Ib operators.png

Standards

  • DefineGive the precise meaning of a word, phrase, concept or physical quantity. the terms: variable, constant, operator, object.
  • DefineGive the precise meaning of a word, phrase, concept or physical quantity. common operators.
  • AnalyseBreak down in order to bring out the essential elements or structure. To identify parts and relationships, and to interpret information to reach conclusions. the use of variables, constants and operators in algorithms.

See Also

References