Let me try and move this forward by answering a question that you did not ask, but perhaps should have. Suppose you have the following input:
XML
<input>
<value>1234567890000000.9</value>
<value>9876543210000000</value>
</input>
and you want to make sure that the input values (which are all numbers, but some of them are not integers) are converted to integers at the output, you could apply the following transformation:
XSLT 1.0
<xsl:stylesheet version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output method="xml" version="1.0" encoding="UTF-8" indent="yes"/>
<xsl:template match="/">
<output>
<xsl:for-each select="input/value">
<value><xsl:value-of select="format-number(., '#')"/></value>
</xsl:for-each>
</output>
</xsl:template>
</xsl:stylesheet>
to obtain the following output:
<?xml version="1.0" encoding="UTF-8"?>
<output>
<value>1234567890000001</value>
<value>9876543210000000</value>
</output>
Note that the results here are rounded, not floored.