ATAN

All functions > MATH > ATAN

Returns the arctangent (inverse tangent) of a number in radians.

Signatures

Returns: Arctangent in radians (between -π/2 and π/2)

ATAN(number: T) → DOUBLE

Notes

• Accepts any real number as input
• Returns values in the range (-π/2, π/2) radians
• ATAN(0) = 0, ATAN(1) = π/4, ATAN(-1) = -π/4
• As input approaches infinity, result approaches π/2
• Returns NULL if input is NULL
• Inverse of TAN function: ATAN(TAN(x)) = x for x in (-π/2, π/2)

Examples

SELECT
    f1 := ATAN(0.0e0),  -- Arctangent of 0
    f2 := ATAN(1.0e0),  -- Arctangent of 1 (45 degrees)
    f3 := ATAN(-1.0e0),  -- Arctangent of -1
    f4 := ATAN(1.732050808e0)  -- Arctangent of sqrt(3)
;