example, to get the first few cubes ordered by the first coordinate
   (lower left corner) ascending one could use the following query:
<programlisting>
SELECT c FROM test ORDER BY c ~&gt; 1 LIMIT 5;
</programlisting>
   And to get 2-D cubes ordered by the first coordinate of the upper right
   corner descending:
<programlisting>
SELECT c FROM test ORDER BY c ~&gt; 3 DESC LIMIT 5;
</programlisting>
  </para>

  <para>
   <xref linkend="cube-functions-table"/> shows the available functions.
  </para>

  <table id="cube-functions-table">
   <title>Cube Functions</title>
    <tgroup cols="1">
     <thead>
      <row>
       <entry role="func_table_entry"><para role="func_signature">
        Function
       </para>
       <para>
        Description
       </para>
       <para>
        Example(s)
       </para></entry>
      </row>
     </thead>

     <tbody>
      <row>
       <entry role="func_table_entry"><para role="func_signature">
        <function>cube</function> ( <type>float8</type> )
        <returnvalue>cube</returnvalue>
       </para>
       <para>
        Makes a one dimensional cube with both coordinates the same.
       </para>
       <para>
        <literal>cube(1)</literal>
        <returnvalue>(1)</returnvalue>
       </para></entry>
      </row>

      <row>
       <entry role="func_table_entry"><para role="func_signature">
        <function>cube</function> ( <type>float8</type>, <type>float8</type> )
        <returnvalue>cube</returnvalue>
       </para>
       <para>
        Makes a one dimensional cube.
       </para>
       <para>
        <literal>cube(1, 2)</literal>
        <returnvalue>(1),(2)</returnvalue>
       </para></entry>
      </row>

      <row>
       <entry role="func_table_entry"><para role="func_signature">
        <function>cube</function> ( <type>float8[]</type> )
        <returnvalue>cube</returnvalue>
       </para>
       <para>
        Makes a zero-volume cube using the coordinates defined by the array.
       </para>
       <para>
        <literal>cube(ARRAY[1,2,3])</literal>
        <returnvalue>(1, 2, 3)</returnvalue>
       </para></entry>
      </row>

      <row>
       <entry role="func_table_entry"><para role="func_signature">
        <function>cube</function> ( <type>float8[]</type>, <type>float8[]</type> )
        <returnvalue>cube</returnvalue>
       </para>
       <para>
        Makes a cube with upper right and lower left coordinates as defined by
        the two arrays, which must be of the same length.
       </para>
       <para>
        <literal>cube(ARRAY[1,2], ARRAY[3,4])</literal>
        <returnvalue>(1, 2),(3, 4)</returnvalue>
       </para></entry>
      </row>

      <row>
       <entry role="func_table_entry"><para role="func_signature">
        <function>cube</function> ( <type>cube</type>, <type>float8</type> )
        <returnvalue>cube</returnvalue>
       </para>
       <para>
        Makes a new cube by adding a dimension on to an existing cube,
        with the same values for both endpoints of the new coordinate.  This
        is useful for building cubes piece by piece from calculated values.
       </para>
       <para>
        <literal>cube('(1,2),(3,4)'::cube, 5)</literal>
        <returnvalue>(1, 2, 5),(3, 4, 5)</returnvalue>
       </para></entry>
      </row>

      <row>
       <entry role="func_table_entry"><para role="func_signature">
        <function>cube</function> ( <type>cube</type>, <type>float8</type>, <type>float8</type> )
        <returnvalue>cube</returnvalue>
       </para>
       <para>
        Makes a new cube by adding a dimension on to an existing cube. This is
        useful for building cubes piece by piece from calculated values.
       </para>
       <para>
        <literal>cube('(1,2),(3,4)'::cube, 5, 6)</literal>
        <returnvalue>(1, 2, 5),(3, 4, 6)</returnvalue>
       </para></entry>
      </row>

      <row>
       <entry role="func_table_entry"><para role="func_signature">
        <function>cube_dim</function> ( <type>cube</type>