SQL Server COS() Function

Summary: in this tutorial, you will learn how to use the SQL Server COS() function to calculate the cosine of a number.

Introduction to the SQL Server COS() function

In SQL Server, the COS() function is a math function that returns the cosine of a number.

The following shows the syntax of the COS() function:

COS(n)Code language: SQL (Structured Query Language) (sql)

In this syntax:

• n is the angle in radians for which you want to find the cosine value.

The COS() function returns the cosine of the argument n. If n is NULL, the COS() function returns NULL.

SQL Server COS() function examples

Let’s explore some examples of using the COS() function.

1) Basic COS() function example

The following example uses the COS() function to calculate the cosine of the number 1 radian:

SELECT COS(1) as cosine_value;Code language: SQL (Structured Query Language) (sql)

Output:

cosine_value
-----------------
0.54030230586814
Code language: SQL (Structured Query Language) (sql)

2) Using the COS() function with PI() function

The following statement uses the COS() function to find the cosine of pi:

SELECT COS(PI()) cosine_value;Code language: SQL (Structured Query Language) (sql)

Output:

cosine_value
------------
-1Code language: SQL (Structured Query Language) (sql)

3) Using COS() function with table data

First, create a table called angles to store angles in radians:

CREATE TABLE angles(
    id INT IDENTITY PRIMARY KEY,
    angle DEC(19,2)
);Code language: SQL (Structured Query Language) (sql)

Second, insert three rows into the angles table:

INSERT INTO
  angles (angle)
VALUES
  (0),
  (PI())
  (PI() / 3);Code language: SQL (Structured Query Language) (sql)

Third, query data from the angles table:

SELECT
  id,
  angle
FROM
  angles;Code language: SQL (Structured Query Language) (sql)

Output:

id | angle
---+------
1  | 0.00
2  | 3.14
3  | 1.05
(3 rows)Code language: SQL (Structured Query Language) (sql)

Finally, calculate the cosines of angles from the angles table:

SELECT
  id,
  COS(angle) cosine_value
FROM
  angles;

Output:

id | cosine_value
---+-------------
1  | 1.0
2  | -1.0
3  | 0.5
(3 rows)Code language: SQL (Structured Query Language) (sql)

Summary

• Use the COS() function to calculate the cosine of a number.