Name
Math.atan2() — compute the angle from the X axis to a point
Synopsis
Math
.
atan2
(
y
,
x
)
Arguments
y
The Y coordinate of the point.
x
The X coordinate of the point.
Returns
A value between -π and π radians that specifies the
counterclockwise angle between the positive X axis and the point
(x
,
y
).
Description
The Math.atan2()
function
computes the arc tangent of the ratio
y
/x
. The
y
argument can be considered the Y
coordinate (or “rise”) of a point, and the
x
argument can be considered the X
coordinate (or “run”) of the point. Note the unusual order of the
arguments to this function: the Y coordinate is passed before the X
coordinate.
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