Beginning XSLT and XPath: Transforming XML Documents and Data

Appendix F. XPath 2.0 Function Reference

This reference provides brief details of the XPath 2.0 functions. These are distinct from functions that apply only to XSLT, which are detailed in Appendix D.

For the authoritative source and for details of the XPath 2.0 operators, go to the W3C recommendation XQuery 1.0 and XPath 2.0 Functions and Operators at www.w3.org/TR/xpath-functions.

You will find further detailed information on the use of these functions, together with additional information on XPath 2.0, in Michael Kay's XSLT 2.0 and XPath 2.0 Programmer's Reference, Fourth Edition (Wrox, 2008).

Functions

abs

Purpose

Returns the absolute value of a number, with the same type as the input.

Signature

abs(value)

Parameter

Name	Description	Type	Use
value	The supplied value	xs:double | xs:float | xs:decimal | xs:integer	Required

avg

Purpose

Returns the average of a sequence of numbers or durations, with the same type as the input.

Signature

avg (sequence)

Parameter

Name	Description	Type	Use
sequence	The supplied value	xs:anyAtomicType	Required

adjust-date-to-timezone, adjust-dateTime-to-timezone, adjust-time-to-timezone

Purpose

Three functions that return a supplied date, datetime, or time, with an altered time zone.

Signature

adjust-date-to-timezone(value, timezone)

Parameters

Name	Description	Type	Use
value	The date, dateTime, or time to adjust	xs:date | xs:dateTime | xs:time	Required
timezone	The time-zone value	xs:dayTimeDuration	Optional

See also

implicit-timezone()

base-uri

Purpose

Returns the base URI of a given document node.

Signature ...