RELAX NG

Name

xsd:duration — Time durations

Synopsis

<xsd:simpleType name="duration” id="duration">
 <xsd:restriction base="xsd:anySimpleType">
 <xsd:whiteSpace value="collapse” fixed="true"/>
 </xsd:restriction>
</xsd:simpleType>

Derived from

xsd:anySimpleType

Primary

xsd:duration

Known subtypes

None

Data parameters (facets)

enumeration, maxExclusive, maxInclusive, minExclusive, minInclusive, pattern

Description

Duration may be expressed using all the parts of a date-time (from year to fractions of second) and are, therefore, defined as a six-dimensional space. Because the relation between some of date parts isn’t fixed (such as the number of days in a month), the order relationship between durations is only partial, and the result of a comparison between two durations may be undetermined.

The lexical space of xsd:duration is the format defined by ISO 8601 under the form:

                  PnYnMnDTnHnMnS

The capital letters are delimiters and can be omitted when the corresponding member isn’t used.

Some durations are undetermined, until a starting point is determined for the duration. The W3C XML Schema relies on this feature to define the algorithm to compare two durations. Four date-times have been chosen that produce the greatest deviations when durations are added. A duration is considered bigger than another when the result of its addition to these four dates is consistently bigger than the result of the addition of the other duration to these same four date-times. These date-times are: 1696-09-01T00:00:00Z, ...