# atan2() Calculates the angle (in radians) from a specified point to the coordinate origin as measured from the positive x-axis. ## Examples
```python def draw(): py5.background(204) py5.translate(py5.width/2, py5.height/2) a = py5.atan2(py5.mouse_y - py5.height/2, py5.mouse_x - py5.width/2) py5.rotate(a) py5.rect(-30, -5, 60, 10) ```
## Description Calculates the angle (in radians) from a specified point to the coordinate origin as measured from the positive x-axis. Values are returned as a float in the range from `PI` to `-PI`. The `atan2()` function is most often used for orienting geometry to the position of the cursor. Note: The y-coordinate of the point is the first parameter, and the x-coordinate is the second parameter, due the the structure of calculating the tangent. This function makes a call to the numpy `atan2()` function. ## Signatures ```python atan2( y: Union[float, npt.ArrayLike], # y-coordinate of the point x: Union[float, npt.ArrayLike], # x-coordinate of the point ) -> Union[float, npt.NDArray] ``` Updated on March 06, 2023 02:49:26am UTC