XPath/XQuery abs function


Returns the absolute value of $arg.


$arg as xs:numeric?
) as xs:numeric?


This function is deterministic, context-independent, and focus-independent.


General rules: see .

If $arg is negative the function returns -$arg, otherwise it returns $arg.

For the four types xs:float, xs:double, xs:decimal and xs:integer, it is guaranteed that if the type of $arg is an instance of type T then the result will also be an instance of T. The result may also be an instance of a type derived from one of these four by restriction. For example, if $arg is an instance of xs:positiveInteger then the value of $arg may be returned unchanged.

For xs:float and xs:double arguments, if the argument is positive zero or negative zero, then positive zero is returned. If the argument is positive or negative infinity, positive infinity is returned.


The expression fn:abs(10.5) returns 10.5.

The expression fn:abs(-10.5) returns 10.5.