math:atan

Returns the arc tangent of the argument, the result being in the range -π/2 to +π/2 radians.

atan($arg as xs:double?) ➔ xs:double?

Namespace

http://www.w3.org/2005/xpath-functions/math

Links to W3C specifications

XPath 3.1 Functions and Operators

Saxon availability

Available in XPath 3.0, XSLT 3.0, XQuery 3.0, and later versions. From Saxon 9.6, available in all editions.

Notes on the Saxon implementation

Implemented since Saxon 9.3; available whether or not XPath 3.0 is enabled. Saxon also (for compatibility) implements the function math:atan() in namespace http://exslt.org/math.