Format Number and Empy Elements

Hi All

You guys helped me out with avoiding empty elements when summing

	Sum(my_node[text()])

Works fantastically, but I'm still plagued by 'NaN' in my output. This
time it's caused by:

	format-number(discount, '$#,.00')

If I have <discount/> in my XML I want to display $0.00 in the output;
however, when discount is an empty element, I get NaN

The only way I can think of to get around it is something like:

<xsl:choose>
	<xsl:when test="string(number(discount))='NaN'">
		Discount: <xsl:value-of select="format-number(0,
$currencyformat)"/>
	</xsl:when>
	<xsl:otherwise>
		Discount: <xsl:value-of select="format-number(discount,
$currencyformat)"/>
	</xsl:otherwise>
</xsl:choose>

Seem awfully long-winded. Anyone got any ideas?

Thanks in advance

M a r k