ceiling() Function  
Returns the smallest integer that is not less than the argument.
 
Inputs

A number. If the argument is not a number, it is transformed into a number as if it had been processed by the number() function. If the argument cannot be transformed into a number, the ceiling() function returns the value NaN (not a number).
 
Output

The smallest integer that is not less than the argument, or NaN if the argument cannot be converted to a number.
 
Defined in

XPath section 4.4, Number Functions.
 
Example

The following stylesheet shows the results of invoking the ceiling() function against a variety of values. We'll use this XML document as input:

<?xml version="1.0"?>
<report>
  <title>Miles Flown in 2001</title>
  <month sequence="01">
    <miles-flown>12379</miles-flown>
    <miles-earned>35215</miles-earned>
  </month>
  <month sequence="02">
    <miles-flown>32857</miles-flown>
    <miles-earned>92731</miles-earned>
  </month>
  <month sequence="03">
    <miles-flown>19920</miles-flown>
    <miles-earned>76725</miles-earned>
  </month>
  <month sequence="04">
    <miles-flown>18903</miles-flown>
    <miles-earned>31781</miles-earned>
  </month>
</report>

Here's the stylesheet that uses the ceiling() function:

<?xml version="1.0"?>
<xsl:stylesheet version="1.0" 
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
  xmlns:months="Lookup table for month names">

  <months:name sequence="01">January</months:name>
  <months:name sequence="02">February</months:name>
  <months:name sequence="03">March</months:name>
  <months:name sequence="04">April</months:name>
  <months:name sequence="05">May</months:name>
  <months:name sequence="06">June</months:name>
  <months:name sequence="07">July</months:name>
  <months:name sequence="08">August</months:name>
  <months:name sequence="09">September</months:name>
  <months:name sequence="10">October</months:name>
  <months:name sequence="11">November</months:name>
  <months:name sequence="12">December</months:name>

  <xsl:output method="text"/>

  <xsl:variable name="newline">
<xsl:text>
</xsl:text>
  </xsl:variable>

  <xsl:template match="/">
    <xsl:value-of select="$newline"/>
    <xsl:text>Tests of the ceiling() function:</xsl:text>

    <xsl:value-of select="$newline"/>
    <xsl:value-of select="$newline"/>
    <xsl:text>   "ceiling('7.983')" = </xsl:text>
    <xsl:value-of select="ceiling('7.983')"/>

    <xsl:value-of select="$newline"/>
    <xsl:text>   "ceiling('-7.893')" = </xsl:text>
    <xsl:value-of select="ceiling('-7.893')"/>

    <xsl:value-of select="$newline"/>
    <xsl:text>   "ceiling(/report/month[@sequence='01']/miles-flown)" = </xsl:text>
    <xsl:value-of select="ceiling(/report/month[@sequence='01']/miles-flown)"/>

    <xsl:value-of select="$newline"/>
    <xsl:text>   "ceiling(document('')/*/</xsl:text>
    <xsl:text>months:name[@sequence='02'])" = </xsl:text>
    <xsl:value-of select="ceiling(document('')/*/months:name[@sequence='02'])"/>

    <xsl:value-of select="$newline"/>
    <xsl:value-of select="$newline"/>
    <xsl:for-each select="/report/month">
      <xsl:text>   </xsl:text>
      <xsl:value-of 
        select="document('')/*/months:name[@sequence=current()/@sequence]"/>
      <xsl:text> - </xsl:text>
      <xsl:value-of select="format-number(miles-flown, '##,###')"/>
      <xsl:text> miles flown, </xsl:text>
      <xsl:value-of select="format-number(miles-earned, '##,###')"/>
      <xsl:text> miles earned.</xsl:text>
      <xsl:value-of select="$newline"/>
      <xsl:text>      (Averaged </xsl:text>
      <xsl:value-of select="ceiling(miles-earned div miles-flown)"/>
      <xsl:text> miles earned for each mile flown.)</xsl:text>
      <xsl:value-of select="$newline"/>
      <xsl:value-of select="$newline"/>
    </xsl:for-each>
  </xsl:template>

</xsl:stylesheet>

When we transform the XML document with our stylesheet, here are the results:


Tests of the ceiling() function:

   "ceiling('7.983')" = 8
   "ceiling('-7.893')" = -7
   "ceiling(/report/month[@sequence='01']/miles-flown)" = 12379
   "ceiling(document('')/*/months:name[@sequence='02'])" = NaN

   January - 12,379 miles flown, 35,215 miles earned.
      (Averaged 3 miles earned for each mile flown.)

   February - 32,857 miles flown, 92,731 miles earned.
      (Averaged 3 miles earned for each mile flown.)

   March - 19,920 miles flown, 76,725 miles earned.
      (Averaged 4 miles earned for each mile flown.)

   April - 18,903 miles flown, 31,781 miles earned.
      (Averaged 2 miles earned for each mile flown.)

Notice that when we invoked the ceiling() function against the string "February" (what document('')/*/months:name[@sequence='02'] resolves to), the function returned NaN. You can compare these results to those from the floor() function and the round() function.