- ATAN Function
- TAN Function
The ATAN2 function returns the arctangent, or inverse tangent, of the specified x- and y-coordinates. The arctangent is the angle from the x-axis to a line containing the origin (0, 0) and a point with coordinates (x_num, y_num). The angle is given in radians between -pi and pi, excluding -pi.
|x_num||The x-coordinate of the point|
|y_num||The y-coordinate of the point|
|2||=ATAN2(1,1)||0.785398163||Arctangent of the point 1,1 in radians, pi/4|
|3||=ATAN2(-1,-1)||-2.35619449||Arctangent of the point -1,-1 in radians, -3*pi/4|
|4||=ATAN2(-1,-1)*180/PI()||-135||Arctangent of the point -1,-1 in degrees|
|5||=DEGREES(ATAN2(-1,-1))||-135||Arctangent of the point -1,-1 in degrees|
Note: If you want the angle returned by the ATAN2 function to be expressed in degrees, you can convert it, using the DEGREES function: =DEGREES(radians)
Note: A positive result represents a counterclockwise angle from the x-axis; a negative result represents a clockwise angle.
Common Function Error(s)
|Problem||What went wrong|
|#VALUE!||Occurs if either of the supplied arguments are non-numeric|
|#DIV/0!||Occurs if the supplied x_num and y_num arguments are both equal to 0|
The arctangent is the inverse of the tangent. Therefore, for the simple right-angle triangle at right, the arctangent of the opposite side (a), divided by the adjacent side (b) is equal to angle A. With coordinates (x,y) located at angle B in the triangle at right, arctangent is calculated as:
See Wikipedia for more information on Inverse Trigonometric Functions.