# math/atan2
Two-argument arc tangent of `y/x`, using the signs of both arguments to determine the quadrant.
## Syntax
[math/atan2 $y $x]
## Parameters
- `$y` — Y coordinate
- `$x` — X coordinate
## Examples
[math/atan2 1 0] # 1.5707963267948966 (π/2) [math/atan2 1 1] # 0.7853981633974483 (π/4) [math/atan2 0 -1] # 3.141592653589793 (π)
## Returns
Number — angle in radians, in the range [-π, π].
## See Also
`math/atan`, `math/hypot`, `math/tan`, `math/pi`