Returns the angle, in radians, whose cosine is the given float expression. Also referred to as arccosine.

ACOS ( float_expression ) 

Arguments

  • float_expression
    An expression of the type float, or of types that can be implicitly converted to float, with a value from -1 through 1. Values outside this range return NULL and report a domain error.

float

Example

The following example returns the arccosine of the cosine of various angles.

CREATE TABLE Acosine ("COS(0)" float, "COS(PI()/6)" float, "COS(PI()/4)" float, "COS(PI()/3)" float, "COS(PI()/2)" float);
INSERT INTO Acosine VALUES (COS(0), COS(PI()/6), COS(PI()/4), COS(PI()/3), COS(PI()/2));
SELECT ACOS ("COS(0)"), ACOS ("COS(PI()/6)"), ACOS ("COS(PI()/4)"), ACOS ("COS(PI()/3)"), ACOS ("COS(PI()/2)")
FROM Acosine;