PHP: Arithmetic Operators

Last update on May 28 2022 12:34:22 (UTC/GMT +8 hours)

Description

There are five basic arithmetic operators.

+ (addition)
- (subtraction)
* (multiplication)
/ (division)
% (modulus)

The operators are summarized in the following table.

Operator	Name	Example	Result
+	Addition	$x + $y	Sum of $x and $y.
-	Subtraction	$x - $y	Difference of $x and $y.
*	Multiplication	$x * $y	Product of $x and $y.
/	Division	$x / $y	Quotient of $x and $y
%	Modulus	$x % $y	Remainder of $x divided by $y.

Example:

<?php
$x=100;
$y=60;
echo "The sum of x and y is : ". ($x+$y) ."<br />";
echo "The difference between x and y is : ". ($x-$y) ."<br />";
echo "Multiplication of x and y : ". ($x*$y) ."<br />";
echo "Division of x and y : ". ($x/$y) ."<br />";
echo "Modulus of x and y : " . ($x%$y) ."<br />";
?>

Output:

The sum of x and y is : 160
The difference between x and y is : 40
Multiplication of x and y : 6000
Division of x and y : 1.6666666666667
Modulus of x and y : 40

View the example in browser

Note : In the case of division, the operator returns a float value if the two operands are not integers.

Previous: PHP Constants
Next: Comparison Operators

PHP: Tips of the Day

How to Sort Multi-dimensional Array by Value?

Try a usort, If you are still on PHP 5.2 or earlier, you'll have to define a sorting function first:

Example:

function sortByOrder($a, $b) {
    return $a['order'] - $b['order'];
}

usort($myArray, 'sortByOrder');

Starting in PHP 5.3, you can use an anonymous function:

usort($myArray, function($a, $b) {
    return $a['order'] - $b['order'];
});

And finally with PHP 7 you can use the spaceship operator:

usort($myArray, function($a, $b) {
    return $a['order'] <=> $b['order'];
});

To extend this to multi-dimensional sorting, reference the second/third sorting elements if the first is zero - best explained below. You can also use this for sorting on sub-elements.

usort($myArray, function($a, $b) {
    $retval = $a['order'] <=> $b['order'];
    if ($retval == 0) {
        $retval = $a['suborder'] <=> $b['suborder'];
        if ($retval == 0) {
            $retval = $a['details']['subsuborder'] <=> $b['details']['subsuborder'];
        }
    }
    return $retval;
});

If you need to retain key associations, use uasort() - see comparison of array sorting functions in the manual

Ref : https://bit.ly/3i77vCC