PHP Manual
Prev |  | Next

# atan2

(PHP 3>= 3.0.5, PHP 4 )

atan2 -- arc tangent of two variables

## Description

float atan2 ( float y, float x)

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).

See also acos() and atan().

Prev | Home | Next
asinh | Up | atan