XML/XML Schema/double

based on type double

File: Data.xml
<?xml version="1.0"?>
<data xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
              xsi:schemaLocation="http://www.wbex.ru Schema.xsd"
              xmlns="http://www.wbex.ru"
              >
   1    
</data>

File: Schema.xsd

<?xml version="1.0"?>
<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema"
  targetNamespace="http://www.wbex.ru" xmlns="http://www.wbex.ru"
  elementFormDefault="qualified">
   <xsd:element name="data" type="thousands"/>
  <xsd:simpleType name="thousands">
    <xsd:restriction base="xsd:double">
      <xsd:maxInclusive value="1e3" />
    </xsd:restriction>
  </xsd:simpleType>
</xsd:schema>