ATAN2

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Syntax

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Scalar

atan2(y, x)

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Arguments

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Returns

• Type: DOUBLE
• Possible values: An angle in radians from -pi through pi.
• NULL behavior: Returns NULL when an argument is NULL.

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Properties

• Approximation bound: No fixed maximum error is guaranteed.

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Units

• Input unit: Coordinates in the same units
• Output unit: Radians
• Use degrees(result) to convert the result to degrees.

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Usage notes

• INTEGER and INT mean the same type; STRING means VARCHAR text. NULL can be used with a supported type. Cast NULL explicitly when its type would otherwise be unclear.
• Exact result: Floating-point computation can round the mathematical result.

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Examples

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Coordinates and NULL input

SELECT atan2(1, 1) AS "value", atan2(CAST(NULL AS DOUBLE), 1) AS null_value;

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Different quadrants

SELECT round(atan2(CAST(1 AS DOUBLE), CAST(1 AS DOUBLE)), 6) AS first_quadrant, round(atan2(CAST(1 AS DOUBLE), CAST(-1 AS DOUBLE)), 6) AS second_quadrant;