diff -u -r1.4 -r1.5
--- lcdd_fields.xsd	31 Aug 2005 18:30:00 -0000	1.4
+++ lcdd_fields.xsd	31 Aug 2005 18:57:28 -0000	1.5
@@ -98,13 +98,43 @@

     </xs:annotation>
     <xs:complexContent>
       <xs:extension base="FieldMapType">

+

 	<xs:sequence>
 	  <xs:element name="rzB" type="RZBType" minOccurs="2" maxOccurs="unbounded" />
 	</xs:sequence>

-	<xs:attribute name="num_bins_r" type="xs:integer" />
-	<xs:attribute name="grid_size_r" type="xs:double" />
-	<xs:attribute name="num_bins_z" type="xs:integer" />
-	<xs:attribute name="grid_size_z" type="xs:double" />

+
+	<xs:attribute name="num_bins_r">
+	  <xs:simpleType>
+	    <xs:restriction base="xs:integer">
+	      <xs:minInclusive value="2"/>
+	    </xs:restriction>
+	  </xs:simpleType>
+	</xs:attribute>
+
+	<xs:attribute name="num_bins_z" type="xs:integer">
+	  <xs:simpleType>
+	    <xs:restriction base="xs:integer">
+	      <xs:minInclusive value="2"/>
+	    </xs:restriction>
+	  </xs:simpleType>
+	</xs:attribute>
+
+	<xs:attribute name="grid_size_r" type="xs:double">
+	  <xs:simpleType>
+	    <xs:restriction>
+	      <xs:minExclusive value="0"/>
+	    </xs:restriction>
+	  </xs:simpleType>
+	</xs:attribute>
+
+	<xs:attribute name="grid_size_z" type="xs:double">
+	  <xs:simpleType>
+	    <xs:restriction>
+	      <xs:minExclusive value="0"/>
+	    </xs:restriction>
+	  </xs:simpleType>
+	</xs:attribute>
+

       </xs:extension>
     </xs:complexContent>
   </xs:complexType>