Re: compare with the preceding value

if youe see the XML file you can see that there are a lot of registro nodes
and for each there is one nombremaquina tag (filed) i this field has the
same value in the preceding registro node i dont want to print but is not
the same value yes.

You can get preceding sibling using preceding-sibling::registro location path.
Try this:
	<xsl:template match="registros">
		<table>
			<xsl:apply-templates/>
		</table>
	</xsl:template>
	<xsl:template match="registro">
		<tr>
			<td>
				<xsl:if test="not(nombremaquina = preceding-sibling::registro/nombremaquina)">
					<xsl:value-of select="nombremaquina"/>
				</xsl:if>
			</td>
		</tr>
	</xsl:template>

--
Oleg Tkachenko
eXperanto team
Multiconn Technologies, Israel