se/SE/schema/WPS_Functions/exslt/math/functions/sqrt/math.sqrt.template.xsl

<?xml version="1.0"?>
<xsl:stylesheet version="1.0"
                xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
                xmlns:math="http://exslt.org/math"
                extension-element-prefixes="math">

<xsl:template name="math:sqrt">
  <!-- The number you want to find the square root of -->
  <xsl:param name="number" select="0" />  
  <!-- The current 'try'.  This is used internally. -->
  <xsl:param name="try" select="1" />
  <!-- The current iteration, checked against maxiter to limit loop count -->  
  <xsl:param name="iter" select="1" />
  <!-- Set this up to ensure against infinite loops -->
  <xsl:param name="maxiter" select="10" />

  <!-- This template was written by Nate Austin using Sir Isaac Newton's
       method of finding roots -->

  <xsl:choose>
    <xsl:when test="$try * $try = $number or $iter > $maxiter">
      <xsl:value-of select="$try"/>
    </xsl:when>
    <xsl:otherwise>
      <xsl:call-template name="sqrt">
        <xsl:with-param name="number" select="$number"/>
        <xsl:with-param name="try" 
                        select="$try - (($try * $try - $number) div (2 * $try))"/>
        <xsl:with-param name="iter" select="$iter + 1"/>
        <xsl:with-param name="maxiter" select="$maxiter"/>
      </xsl:call-template>
    </xsl:otherwise>
  </xsl:choose>
</xsl:template>

</xsl:stylesheet>