ACOS

Description

Function that returns the arccosine in radians of the number sent as a parameter (ACOS in Transact-SQL).

Mathematically, the arccosine is the inverse function of the cosine, resulting in the following definition: $y = cos^{-1} \Leftrightarrow x = cos(y)$

For $y = cos^{-1}(x)$: - Range: $0\leqslant y \leqslant \pi$ or $0^{\circ}\leqslant y \leqslant 180^{\circ}$ - Domain: $-1\leqslant x \leqslant 1$

Sample Source Pattern

Syntax

ACOS ( expression )

Arguments

expression: Numeric float expression, where expression is in$[-1,1]$.

Return Type

Numeric float expression between 0 and π. If the numeric expression sent by parameter is out of the domain $[-1, 1]$, the database engine throws an error.

Examples

Query

SELECT ACOS(-1.0);

Result

ACOS(-1.0)       |
-----------------+
3.141592653589793|