php / 8.1.5 / function.atan2.html /

atan2

(PHP 4, PHP 5, PHP 7, PHP 8)

atan2Arc tangent of two variables

Description

atan2(float $y, float $x): float

This function calculates the arc tangent of the two variables x and y. It is similar to calculating the arc tangent of y / x, except that the signs of both arguments are used to determine the quadrant of the result.

The function returns the result in radians, which is between -PI and PI (inclusive).

Parameters

y

Dividend parameter

x

Divisor parameter

Return Values

The arc tangent of y/x in radians.

See Also

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https://www.php.net/manual/en/function.atan2.php