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atan2

1. ATAN2 Function​

The ATAN2 function in H2 database is used to calculate the arctangent of the quotient of two specified numbers.

2. Syntax​

The syntax for the ATAN2 function in H2 database is as follows:

ATAN2(y, x)

Arguments​

  • y: The numerator value.
  • x: The denominator value.

Return​

  • The ATAN2 function returns the arctangent of the quotient y/x, in the range -π to π.

3. Notes​

  • The ATAN2 function calculates the arctangent of the quotient y/x, taking into account the signs of both arguments to determine the correct quadrant of the result.
  • The result of the ATAN2 function is in radians.
  • If both x and y are zero, the ATAN2 function returns zero.
  • If x is zero and y is non-zero, the ATAN2 function returns π/2 if y is positive, or -π/2 if y is negative.

4. Examples​

Here are a few examples demonstrating the usage of the ATAN2 function in H2 database:

Example 1 - Calculating the arctangent of a quotient:​

SELECT ATAN2(1, 2) AS arctangent;

Output:

arctangent
----------
0.4636476090008061

Example 2 - Calculating the arctangent of quotients stored in columns:​

CREATE TABLE fractions (
  id INT PRIMARY KEY,
  numerator DOUBLE,
  denominator DOUBLE
);

INSERT INTO fractions VALUES (1, 3, 4), (2, 5, 6), (3, -1, -2);

SELECT id, numerator, denominator, ATAN2(numerator, denominator) AS arctangent
FROM fractions;

Output:

id | numerator | denominator |      arctangent
---+-----------+-------------+---------------------
1  | 3         | 4           | 0.643501109 rad
2  | 5         | 6           | 0.6957702405 rad
3  | -1        | -2          | -0.463647609 rad
  • atan - Calculate arctangent
  • tan - Calculate tangent