ATAN2 returns a trigonometric arc tangent (inverse tangent) for two values X and Y, which are the lengths of the rectangular sides of a triangle.

Syntax

ATAN2(NumExp for X, NumExp for Y)

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• NumExp for X is the length of one rectangular side of a triangle corresponding with the co-ordinate values.
• NumExp for Y is the length of the other rectangular side of a triangle corresponding with the co-ordinate values.

Remarks

1. ATAN2 produces the true angle corresponding with the X,Y co-ordinates (the arguments) whereas ATAN produces an angle only on the basis of Y/X which leaves the quadrant unknown (please note that in those cases two solutions are possible for one Y/X value).
2. The result is in Radians.

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