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?

Arguments
	$arg	xs:double?	The supplied angle in radians
Result		xs:double?

Details

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

Applies to: XPath 3.0, XSLT 3.0, XQuery 3.0 (if enabled in Saxon: requires Saxon-PE or Saxon-EE)

Notes on the Saxon implementation

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