XPath/XQuery abs function

Returns the absolute value of $arg.

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.