ACOS()

All functions > MATH > ACOS()

Returns the arccosine (inverse cosine) of a number, in radians.

Signatures

Arccosine

Returns: Angle in radians, in [0, π]

ACOS(number: T) → DOUBLE

With:

• T : Floating-point type (FLOAT, DOUBLE)

Signature notes:

• Input must be in [-1, 1]
• ACOS(1.0) = 0, ACOS(-1.0) = π, ACOS(0.0) = π/2
• Returns NaN for inputs outside [-1, 1]
• Returns NULL if the input is NULL

Examples

SELECT
    f1 := ACOS(1.0E0), -- acos(1) = 0
    f2 := ACOS(0.5E0), -- acos(0.5) = π/3
    f3 := ACOS(0.0E0), -- acos(0) = π/2
    f4 := ACOS(-1.0E0) -- acos(-1) = π
;