[xsl] Counting preceding nodes

["Kevin Bird" <kevin.bird@xxxxxxxxxxxxxxxxxxxxxxx>]

Hi

I have the following XML structure, <level3/> is my context node. I want
to count the preceding <level3/> nodes that have the same <level1>
grandparent. I can't seem to get my head around the XPATH syntax.

<wrapper>
<level1>
	<level2>
		<level3/>
	</level2>
	<level2>
		<level3/>
	</level2>
	<level2>
		<level3/>
	</level2>
</level1>
<level1>
	<level2>
		<level3/>
	</level2>
	<level2>
		<level3/>
	</level2>
	<level2>
		<level3/>	<!-- when context, preceding count will
be 2 -->
	</level2>
	<level2>
		<level3/>	<!-- when context, preceding count will
be 3 -->
	</level2>
</level1>
</wrapper>

Thanks.

--
Kevin