Re: XPath / XSLT 2.1 - Rounding algorithms

A couple of years ago, I ran into a need to call extension functions
to round numbers in the "traditional" way: to round half up for results of
.5 (or more). I found that it was only possible with XSLT to round to the even
number.

Specifically, round-half-up(decimal_num,num_digits), where 'up' means towards
positive or negative infinity, is what I'm looking for.

T:\ftemp>type peter.xsl
<?xml version="1.0" encoding="US-ASCII"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
                xmlns:xsd="http://www.w3.org/2001/XMLSchema"
                xmlns:c="urn:X-Crane"
                exclude-result-prefixes="xsd c"
                version="2.0">

<xsl:template match="/">
-2.5: <xsl:value-of select="c:PeterRound(-2.5)"/>
2.5:  <xsl:value-of select="c:PeterRound(2.5)"/>
</xsl:template>

<xsl:function name="c:PeterRound">
  <xsl:param name="x"/>
  <xsl:sequence select="if( $x &lt; 0 ) then -( round(abs($x)) )
                                        else round($x)"/>
</xsl:function>

</xsl:stylesheet>
T:\ftemp>xslt2 peter.xsl peter.xsl con

-2.5: -3
2.5:  3
T:\ftemp>

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