_ATAN2
From QB64 Wiki
The _ATAN2 function returns the radian angle between the positive x-axis of a plane and the point given by the coordinates (x, y).
- angle! = _ATAN2( y, x)
- y is the vertical axis position(row) as a positive, zero or negative floating point value.
- x is the horizontal axis position(column) as a positive, zero or negative floating point value.
Description:
- The DOUBLE radian angle returned is positive for upper row values where y > 0.
- The DOUBLE radian angle returned is 0 when x > 0 and _PI when x < 0 where y = 0
- The DOUBLE radian angle returned is negative for lower row values where y < 0.
- _ATAN2(0, 0) is undefined and the function returns 0 instead of a division error.
See also:
- ATN (arctangent)
- _PI (QB64 function)
- Mathematical Operations
- Atan2 reference