ZVON > Tutorials > XML Schema and Relax NG Tutorial
Intro / Search / ZVON
Index | >> Example 4 / 8 << | Prev | Next |
Contents > Definition of own types > Limiting both the number of decimal places and total places

Limiting both the number of decimal places and total places

  1. XML Schema
  2. Relax NG

Please, send all comments, bug-reports, and contributions to Jiri.Jirat@systinet.com. Thank you very much.

XML Schema keys: decimal, totalDigits, fractionDigits

1. XML Schema

The element "A" represents a number in the format xxx.xx or -xxx.xx. It must have max. two decimal places and must have 5 total digits. We will define our custom type "myNumber" using "totalDigits" and "fractionDigits" elements. The element "A" must be of that type.

Valid document


<A xsi:noNamespaceSchemaLocation="correct_0.xsd" xmlns="" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" >999.99</A>

Valid document


<A xsi:noNamespaceSchemaLocation="correct_0.xsd" xmlns="" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" >-123.50</A>

Invalid document
There are too many both total and decimal places.


<A xsi:noNamespaceSchemaLocation="correct_0.xsd" xmlns="" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" >9999.9999</A>

Invalid document
The number of decimal places is too high (must be less or equal to 2).


<A xsi:noNamespaceSchemaLocation="correct_0.xsd" xmlns="" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" >99.999</A>

Correct XML Schema (correct_0.xsd)


<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema" >

  <xsd:element name="A" type="myNumber"/>

  <xsd:simpleType name="myNumber">
    <xsd:restriction base="xsd:decimal">
      <xsd:totalDigits value="5"/>
      <xsd:fractionDigits value="2"/>
    </xsd:restriction>
  </xsd:simpleType>
</xsd:schema>

2. Relax NG

The element "A" represents a number in the format xxx.xx or -xxx.xx. It must it must have two decimal places and must have 5 total digits. We will use the "decimal" datatype from XML Schemas and restrict it using using "totalDigits" and "fractionDigits". The element "A" must contain this pattern.

Valid document


<A xmlns="">999.99</A>

Valid document


<A xmlns="">-123.50</A>

Invalid document
There are too many both total and decimal places.


<A xmlns="">9999.9999</A>

Invalid document
The number of decimal places is too high (must be less or equal to 2).


<A xmlns="">99.999</A>

Correct Relax NG schema (correctRelax_0.rng)


<grammar datatypeLibrary="http://www.w3.org/2001/XMLSchema-datatypes" xmlns="http://relaxng.org/ns/structure/1.0" >

  <start>
    <element>
      <name ns="">A</name>
      <ref name="myNumber"/>
    </element>
  </start>

  <define name="myNumber">
    <data type="decimal">
      <param name="totalDigits">5</param>
      <param name="fractionDigits">2</param>
    </data>
  </define>
</grammar>