Learn
PHP Numbers
Review
Great job! In this lesson, we learned all about using numbers in PHP. Let’s review what we covered:
- PHP has two number data types: integers and floating point numbers
- We can use arithmetic operators for performing math operations:
Operation: | Example: | |
---|---|---|
Addition | + |
echo 1 + 4.5; // Prints: 5.5 |
Subtraction | - |
echo 9 - 1; // Prints: 8 |
Multiplication | * |
echo -1.9 * 2.9; // Prints: -5.51 |
Division | / |
echo 9 / 1; // Prints: 9 |
Modulo | % |
echo 11 % 3; // Prints: 2 |
Exponentiation | ** |
echo 8**2; // Prints: 64 |
- Operations have an order of precedence meaning that certain types of operations in a chain will be evaluated before others: first evaluated will be any operation wrapped in parenthesis (
()
), next exponents (**
), then multiplication (*
) and division (/
), and finally addition (+
) and subtraction (-
). The acronym PEMDAS can be a helpful way of remembering the order. - We can assign number values to variables and then perform numerical operations with them.
- We can use mathematical assignment operators as a shorthand when reassigning number variables:
Operation: | Long Syntax: | Short Syntax: |
---|---|---|
Add | $x = $x + $y | $x += $y |
Subtract | $x = $x - $y | $x -= $y |
Multiply | $x = $x * $y | $x *= $y |
Divide | $x = $x / $y | $x /= $y |
Mod | $x = $x % $y | $x %= $y |