atan

atan is useful when you want to map a numeric value from an unbounded range to a bounded angular range (-π/2, π/2). For example, you can use atan to normalize latency deviations, scores, or ratios into a smooth angle scale for comparison or encoding.

Usage#

Syntax#

atan(x)

Parameters#

Name	Type	Required	Description
`x`	real	Yes	A real number.

Returns#

The arc tangent of x in radians, in the range (-π/2, π/2).

Example#

Use atan to compute the arctangent of a value and return the angle in radians.

Query

print result = atan(1)

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Output

result
0.7854

atan2: Returns the arc tangent using two arguments (y, x). Use it when you have separate numerator and denominator values.
asin: Returns the arc sine. Use it when the input is bounded to [-1, 1].
acos: Returns the arc cosine. Use it when you need the inverse cosine instead.
tan: Returns the tangent. Use it to apply the forward transformation before using atan as the inverse.
radians: Converts degrees to radians. Use it when your angle data is in degrees.

Other query languages#

Splunk SPL users

In Splunk SPL, atan() is available in the eval command with the same behavior: it returns the arc tangent in radians for any real number input.

Splunk example

| eval angle = atan(normalized)

APL equivalent

['sample-http-logs']
| extend angle = atan(normalized)

ANSI SQL users

In ANSI SQL, ATAN() is a standard mathematical function with identical semantics. It accepts any real number and returns the arc tangent in radians.

SQL example

SELECT ATAN(normalized) AS angle FROM logs