[xsl] Concatenate and unique values

Hi All

SymptomNum is sequential from 0 till the number of rows of data. Each row has SymptomNum, Pulse and Heart-beat. Across all the SymptomNum, I want to find the unqiue combinations of Pulse and Heart-beat existing in the data. There may be repitions, so I want to ignore them.

<xsl:for-each select="//Health/Disease[(./SymptomNum)>=0]">

<xsl:variable name="current-sym-num" select="./SymptomNum"/>

<xsl:variable name="pulse-val" select="./Pulse"/>

<xsl:variable name="heart-beat-val" select="./HeartBeat"/>

<xsl:variable name="sym-summary" select="concat($pulse-val, ' ', $heart-beat-val)"/> 

<!-- Display all unique combinations of pulse-val and heart-beat-val -->

<xsl:if test="$pulse-val and $heart-beat-val">

    How do i find that this current combination of pulse-val and heart-beat-val is unique?

</xsl:if>

</xsl:for-each>

I have been using this logic to get unique values of pulse values:

<xsl:variable name="unique-pulse-num" select="//Health/Disease/Pulse[not(.=following::Pulse)]" />

<xsl:for-each select="$unique-pulse-num">

    <xsl:value-of select="." />, 

</xsl:for-each>

Can this logic be extended to multiple attributes of an element? Can anyone help me with this logic? Thanks in advance,

Pragyan