Published Jun 21, 2023
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The SQL function ACOS() calculates the arccosine of a given value, expressed in radians.



value is the number, for which the arccosine is calculated. This input value must be between -1 and 1, or the function will return NULL.

Note: The output value of the ACOS() function uses radians, not degrees. To convert radians to degrees, the radian value can be multiplied by 180/π.


The following example uses the data given in the table values:

id input_value
1 0.8
2 1
3 -0.5

The ACOS() function is used to calculate the arccosine as the output_value:

SELECT id, input_value, ACOS(input_value) AS output_value
FROM values;

The output will be:

id input_value output_value
1 0.8 0.643501109
2 1 0
3 -0.5 2.0943951

Note: For the use of this method with SQL databases like MySQL, SQLite, PostgreSQL, or SQL Server, refer to their respective documentation for more details on the ACOS() function implementation and compatibility.

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