Operators: Difference between revisions

Latest revision as of 16:05, 2 September 2023

Programming basics^[1]

An operator is symbol 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

Assignment operators[edit]

An assignment operator assigns a value to its left operand based on the value of its right operand.^[3]

Arithmetic operators[edit]

Arithmetic operators take numerical values (either literals or variables) as their operands and return a single numerical value. The standard arithmetic operators are addition (+), subtraction (-), multiplication (*), and division (/).^[4]

An example of some arithmetic operators in PHP can be found below ^[5].

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.

An example of some arithmetic operators in Python can be found below ^[6].

Example	Name	Result
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.

Comparison operators[edit]

Comparison operators, as their name implies, allow you to compare two values.^[7]

An example of some conditional operators in PHP can be found below ^[8].

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 integer 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.

An example of some conditional operators in Python can be found below ^[9].

Example	Name	Result
a == b	Equal	TRUE if a is equal to b
a != b	Not equal	TRUE if a is not equal to b
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 in b	in	TRUE if a is in b.
a not in b	not in	TRUE if a is NOT in b

A video[edit]

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[edit]

Please know all code submitted to the IB (with the exception of object oriented programming option) 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.

Python operators cheatsheet[edit]

Click here for an excellent python cheatsheet

Standards[edit]

Define the terms: variable, constant, operator, object.
Define common operators.
Analyse the use of variables, constants and operators in algorithms.

References[edit]

[1] ttp://www.flaticon.com/

[2] ttp://php.net/manual/en/language.operators.php

[3] ttps://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Assignment_Operators

[4] ttps://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Arithmetic_Operators

[5] ttp://php.net/manual/en/language.operators.arithmetic.php

[6] ttps://www.geeksforgeeks.org/basic-operators-python/

[7] ttps://www.php.net/manual/en/language.operators.comparison.php

[8] ttp://php.net/manual/en/language.operators.comparison.php

[9] ttps://www.geeksforgeeks.org/basic-operators-python/

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@@ Line 1: / Line 1: @@
-<center>
-<blockquote style="padding: 5px; background-color: #FFF8DC; border: solid thin gray;">
-   [[File: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.
-</blockquote>
-</center>
 [[file:arrows.png|right|frame|Programming basics<ref>http://www.flaticon.com/</ref>]]
-Arrays are a fundamental data structure, and they are extremely useful. We use arrays to hold values of the same type at contiguous memory locations. In particular, the use of arrays allows us to create "groups" or "clusters" of variables without needing to give a unique variable name to each, but still allowing us to individually index into the elements of the array. If you haven't started counting from zero yet, now is the time, because in C, arrays are zero-indexed which means the first element of a k-element array is located at array index 0 and the last element is located at array index k-1. In case you're wondering, that's the primary reason we count from 0 in CS50 (and in computer science more broadly!)<ref>http://cs50.wiki/Arrays+and+strings</ref>
+An operator is symbol that takes one or more values (or expressions, in programming jargon) and yields another value (so that the construction itself becomes an expression)<ref>http://php.net/manual/en/language.operators.php</ref>.
-In an array we are usually concerned about 2 things, the '''position''' of a piece of data and the actual data.
+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, [http://php.net/manual/en/language.operators.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
-An example of a simple array in PHP can be found below:
-<syntaxhighlight lang="php"  line>
+== Assignment operators ==
-<?php
+An assignment operator assigns a value to its left operand based on the value of its right operand.<ref>https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Assignment_Operators</ref>
-# this file  is used to teach the VERY BASICS of arrays in PHP
-$pizza_toppings = array (
+== Arithmetic operators ==
-"extra cheese"
-"onions"
-"pepperoni"
-"ham"
-"pineapple"
-"chicken"
-"arugula"
-"pesto"
-);
-# This creates a very simple array with 8 items.
+Arithmetic operators take numerical values (either literals or variables) as their operands and return a single numerical value. The standard arithmetic operators are addition (+), subtraction (-), multiplication (*), and division (/).<ref>https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Arithmetic_Operators</ref>
-?>
+An example of some '''arithmetic''' operators in PHP can be found below <ref>http://php.net/manual/en/language.operators.arithmetic.php</ref>.
-</syntaxhighlight>
+{| style="width: 95%;" class="wikitable"
+|-
+!Example	!! Name	!! Result
+|-
+| +$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 $b'th power.
+|}
+An example of some '''arithmetic''' operators in Python can be found below <ref>https://www.geeksforgeeks.org/basic-operators-python/</ref>.
+{| style="width: 95%;" class="wikitable"
+|-
+!Example	!! Name	!! Result
+|-
+| a + b	||Addition||	Sum of a and b.
+|-
+| a - b||	Subtraction	||Difference of a and b.
+|-
+| a * b||Multiplication||	Product of a and b.
+|-
+| a / b||	Division||	Quotient of a and b.
+|-
+| a % b||Modulus||	Remainder of a divided by b.
+|-
+| a ** b	||Exponentiation||	Result of raising a to the b'th power.
+|}
+== Comparison operators ==
+Comparison operators, as their name implies, allow you to compare two values.<ref>https://www.php.net/manual/en/language.operators.comparison.php</ref>
+An example of some '''conditional''' operators in PHP can be found below <ref>http://php.net/manual/en/language.operators.comparison.php</ref>.
+{| style="width: 95%;" class="wikitable"
+|-
+!Example	!! Name	!! Result
+|-
+|$a == $b	||Equal	||TRUE if $a is equal to $b after [http://php.net/manual/en/language.types.type-juggling.php type juggling.]
+|-
+|$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 $b after [http://php.net/manual/en/language.types.type-juggling.php type juggling.].
+|-
+|$a <> $b||	Not equal||	TRUE if $a is not equal to $b after [http://php.net/manual/en/language.types.type-juggling.php type juggling.]
+|-
+|$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 integer 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.
+|}
+An example of some '''conditional''' operators in Python can be found below <ref>https://www.geeksforgeeks.org/basic-operators-python/</ref>.
+{| style="width: 95%;" class="wikitable"
+|-
+!Example	!! Name	!! Result
+|-
+|a == b	||Equal	||TRUE if a is equal to b
+|-
+|a != b||	Not equal||	TRUE if a is not equal to b
+|-
+|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 in b || in || TRUE if a is in b.
+|-
+| a not in b || not in || TRUE if a is NOT in b
+|}
 == A video ==
@@ Line 47: / Line 139: @@
 == The way the IB wants you to use operators ==
-Please know all code submitted to the IB (with the exception 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.
+Please know all code submitted to the IB (with the exception of object oriented programming option) is in [[pseudocode]]. The way we write operators in [[pseudocode]] is different than the way we might write them in the real world.
+[[:media:Approved notation for developing pseudocode.pdf | 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.
-[[:File:Approved notation for developing pseudocode.pdf | Click here to view a file describing operators. This is the approved notation sheet from the IB.]]
+[[File:Ib operators.png]]
-== Standards ==
+== Python operators cheatsheet ==
-* Construct algorithms using pre- defined sub-programmes, one- dimensional arrays and/or collections.
+[[:File:Python3 reference cheat sheet.pdf|Click here for an excellent python cheatsheet]]
-== See Also ==
+== Standards ==
-* [[Conditionals in php]]
+* Define the terms: variable, constant, operator, object.
+* Define common operators.
+* Analyse the use of variables, constants and operators in algorithms.
 == References ==