PLSQL | ACOS Function

The PLSQL ACOS function is used to return the arc cosine of a number. The ACOS function only one parameter which is a number and the argument number must be in the range of -1 to 1, and the function returns a value in the range of 0 to pi, expressed in radians.

This function takes as an argument any numeric data type or any non-numeric data type that can be implicitly converted to a numeric data type.

Syntax:

ACOS( number )

Parameters Used:

number – It is used to specify the number arc cosine needs to be calculated.

Return Value:
The ACOS function in PLSQL returns a numeric value.

Supported Versions of Oracle/PLSQL:

1. Oracle 12c
2. Oracle 11g
3. Oracle 10g
4. Oracle 9i
5. Oracle 8i

Example-1: Using a positive numeric value as an argument in the ACOS function.

DECLARE 
   Test_Number number := 0.5;
   
BEGIN 
   dbms_output.put_line(ACOS(Test_Number)); 
   
END; 

Output:

1.04719755119659774615421446109316762805 

Example-2: Using a negative numeric value as an argument in the ACOS function.

DECLARE 
   Test_Number number := -0.5;
   
BEGIN 
   dbms_output.put_line(ACOS(Test_Number)); 
   
END;  

Output:

2.09439510239319549230842892218633525615 

Example-3: Using a numeric value which doesn’t fall in the range between -1 and 1 as an argument in the ACOS function.

DECLARE 
   Test_Number number := 4.5;
   
BEGIN 
   dbms_output.put_line(ACOS(Test_Number)); 
   
END;   

Output:

ERROR
ORA-01428: argument '4.5' is out of range 

The above program throws an error since the argument passed is exceeding the range which can be accepted.

Example-4: Using ACOS function with select query.

SELECT ACOS(.3) FROM dual; 

Output:

0.3046926540153975 

Example-5: Using ACOS function with select query and returning the value in degree.

select (ACOS(.4)) * 57.29  FROM dual; 

Output:

66.41512145087323 

Using the conversion formula of 1 radian = 57.29 degrees.

Advantages:
The ACOS function accepts any numeric datatype or any non-numeric datatype as an argument that can be implicitly converted to a numeric datatype.