tan ↗

Use the tan() function to calculate the tangent of a numeric value specified in radians.

Syntax

tan(<numeric_expression>)

Parameters

Name Type Required Description
numeric_expression integer, float Yes The angle in radians for which to calculate the tangent. Any real number is valid, though the tangent is undefined at odd multiples of p/2.

Returns

Type: float

Description: The tan() function returns the tangent of the input angle. The result can be any real number. If the input is null, the function returns null.

Usage notes

  • Input type: XQL doesn't support NaN or infinite values as input and these value types also can not be returned.
  • Valid Input Range: The tan() function accepts any real number as input. The input is interpreted as an angle in radians.
  • Undefined Values: At odd multiples of p/2 (for example, p/2, 3p/2), the tangent is mathematically undefined and the function may return a very large number, infinity, or NaN.
  • Null Handling: If the input expression is null, the function returns null.
  • Degrees to Radians: If your input is in degrees, convert it to radians first by multiplying by PI() / 180.
  • Periodicity: The tangent function is periodic with period p, meaning tan(x) = tan(x + p).
  • Key Values: tan(0) returns 0.0, tan(p/4) returns 1.0, tan(p) returns 0.0.
  • Symmetry: The function is odd, meaning tan(-x) = -tan(x).
  • Common Use Cases: This function is typically used within the alter stage for trigonometric calculations, slope computations, angle analysis, and engineering formulas.

Examples

Example 1: Calculate tangent of literal values

Goal: Calculate the tangent for specific radian values to verify known mathematical results.

XQL code:

dataset = xdr_data
| limit 1
| alter result1 = tan(0), result2 = tan(divide(pi(), 4)), result3 = tan(pi())
| fields result1, result2, result3

Explanation: tan(0) returns 0.0, tan(p/4) returns 1.0 (since sine and cosine are equal at p/4), and tan(p) returns approximately 0.0.

Output:

RESULT1 RESULT2 RESULT3
0.0 1.0 0.0

Example 2: Calculate tangent from a field value

Goal: Calculate the tangent of values stored in a dataset field, treating them as angles in radians.

XQL code:

config timeframe = 1d
| dataset = sample_xql_raw
| alter tan_val = tan(numeric_value)
| fields event_id, numeric_value, tan_val
| limit 3

Explanation: This query computes the tangent for each value in the numeric_value field and stores the result in tan_val. Since tan() accepts any real number, no filtering is needed.

Output:

EVENT_ID NUMERIC_VALUE TAN_VAL
101 0.0 0.0
102 0.7854 1.0
103 1.0 1.55741

Example 3: Calculate slope angle from rise and run

Goal: Use the tangent function to verify a slope calculation by computing tan(atan(rise/run)).

XQL code:

config timeframe = 1d
| dataset = sample_xql_raw
| filter duration_seconds > 0
| alter slope = divide(numeric_value, duration_seconds)
| alter angle = atan(slope)
| alter tan_angle = tan(angle)
| fields event_id, numeric_value, duration_seconds, slope, tan_angle
| limit 3

Explanation: This query calculates the slope as numeric_value / duration_seconds, then computes the angle using atan(), and finally verifies by computing tan() of that angle. The tan_angle should match the original slope, confirming the identity tan(atan(x)) = x.

Output:

EVENT_ID NUMERIC_VALUE DURATION_SECONDS SLOPE TAN_ANGLE
101 3.0 4.0 0.75 0.75
102 5.0 1.0 5.0 5.0
103 10.0 10.0 1.0 1.0