Arithmetic Operators

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- Arithmetic Operators

## Arithmetic Operators

Remember basic arithmetic from school? These work just like those.

Arithmetic Operators
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` | Modulo | Remainder of $a divided by $b.
`$a ** $b` | Exponentiation | Result of raising $a to the $b'th power.

The division operator `/` returns a float value unless the two operands are int (or numeric strings which are type juggled to int) and the numerator is a multiple of the divisor, in which case an integer value will be returned. For integer division, see intdiv().

Operands of modulo are converted to int before processing. For floating-point modulo, see fmod().

The result of the modulo operator `%` has the same sign as the dividend — that is, the result of `$a % $b` will have the same sign as $a. For example:

    <?php

    var_dump(5 % 3);
    var_dump(5 % -3);
    var_dump(-5 % 3);
    var_dump(-5 % -3);

    ?>

The above example will output:

    int(2)
    int(2)
    int(-2)
    int(-2)

### See Also

- Math functions