Add DateTime and duration confused

geek.shrek · November 30th, 2009, 01:22 AM

Hi,

I'm using xslt 2.0

How can I add dateTime and duration?
I would like to check if the data start for example at 15:00:00.
my idea was to add the start and data duration.

my xml data

Code:

<mydatacollection>
    <data_header>
       <start>2010-02-11T00:00:00</start>
    <data_header>
    <data id="ABC123">
      <duration>00:01:00:00</duration>
    </data>
</mydatacollection>

so far I have this and try to add the duration with exslt and it's show me an error "unknown function".
I think I'm a bit (maybe more) confused

.

Code:

<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:xs="http://www.w3.org/2001/XMLSchema" 
    xmlns:date="http://exslt.org/dates-and-times"
    xmlns:str="http://exslt.org/strings"
    version="2.0">
...
<xsl:template match="data">
<xsl:element name="test">
                <xsl:variable name="dur" select="/duration"></xsl:variable>
                <xsl:variable name="tokens"><xsl:value-of select="str:split($dur)"/></xsl:variable>
                <xsl:variable name="hour"><xsl:value-of select="tokens/token"/></xsl:variable>
                <xsl:variable name="minute"><xsl:value-of select="tokens/token"/></xsl:variable>
                <xsl:variable name="second"><xsl:value-of select="tokens/token"/></xsl:variable>
                <xsl:value-of select="date:add(//data_header/start,$hour)"></xsl:value-of>
            </xsl:element>

</xsl:template>

Can someone point me on how can I add duration and timedate.

Thanks,

Martin Honnen · November 30th, 2009, 08:16 AM

The arithmetic operations on dateTime/durations that XPath 2.0 allows are defined here: http://www.w3.org/TR/xquery-operator...ime-arithmetic
So you can add a dayTime duration to a dateTime, and you can add a yearMonthDuration to a dateTime.
An example would be

Code:

<xsl:stylesheet
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
  xmlns:xs="http://www.w3.org/2001/XMLSchema"
  version="2.0"
  exclude-result-prefixes="xs">
  
  <xsl:template name="main">
    <xsl:value-of select="xs:dateTime('2010-02-11T00:00:00') + xs:dayTimeDuration('P0DT1H')"/>
  </xsl:template>

</xsl:stylesheet>

mhkay · November 30th, 2009, 09:37 AM

You don't need EXSLT for this if you're using XSLT 2.0 - you can just use the "+" operator, so long as the operands are the right type.

Note that the format for durations is PT1H, not 00:01:00:00. If your input has to be in this format, you could treat 01:00:00 as an xs:time value, and then subtract xs:time('00:00:00') to get the interval as a duration.

geek.shrek · November 30th, 2009, 11:38 AM

Thanks for the tips :)
Unfortunately I can't change the duration format, it has to be "00:00:00:00"
So I will try to truncate the last ":00"

geek.shrek · November 30th, 2009, 05:55 PM

Code:

<xsl:element name="dur">
       <xsl:variable name="dur" select="fn:substring(duration,0,9)"/>
       <xsl:value-of select="xs:time($dur) - xs:time('00:00:00')"></xsl:value-of>
</xsl:element>

but the xs:time($dur) result as an error "Error in XPath 2.0 expression Cast failed, invalid lexical value - xs:time"

Is it because fn:substring return as a string with " ?

When I tried with for example <xsl:value-of select="xs:time('00:04:00') - xs:time('00:00:00')"></xsl:value-of>

it was ok. Is " ' " make a difference in xs:time?

Thanks so much.

mhkay · November 30th, 2009, 06:19 PM

I think you're guessing that substring() in XPath behaves like substring() in Java. It doesn't. You want 8 characters starting at position 1, which is substring(x, 1, 8). (Or do you? I don't know your data, but my guess would have been 8 characters starting at position 4).

geek.shrek · November 30th, 2009, 07:01 PM

Yes, I missed that detail that xpath start the character from 1. Thanks for that.

but It still show the same error.

My duration is for example "00:40:00:00", so I was thinking to remove the last ":00" and cast as xs:time as your tips before. I've checked the output of $dur is "00:40:00" just as I wanted. but when I cast to xs:time($dur) it came out as "Error in XPath 2.0 expression Cast failed, invalid lexical value - xs:time"

mhkay · November 30th, 2009, 07:07 PM

Can't see the reason for this error from the information provided. Please post a complete (but minimal) XML and XSLT that illustrate the problem.

geek.shrek · November 30th, 2009, 07:14 PM

Here is my data

Code:

<mydatacollection>
       <data_header>
             <start>2010-02-11T00:00:00</start>
   <data_header>
   <data id="ABC123">
           <duration>00:01:00:00</duration> 
   </data>
</mydatacollection>

Here is my xslt

Code:

<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:xs="http://www.w3.org/2001/XMLSchema" 
xmlns:fn="http://www.w3.org/2005/xpath-functions"
    version="2.0">

<xsl:template match="data">
   <xsl:element name="dur">
           <xsl:variable name="dur" select="fn:substring(duration,1,8)"/>
            <xsl:value-of select="xs:time($dur)"></xsl:value-of>  <!-- the error came up here -->
    </xsl:element>
     <xsl:element name="test">
                <xsl:variable name="dur" select="fn:substring(duration,0,9)"/>
                <xsl:value-of select="xs:dateTime(ancestor-or-self::node()/mydatacollection/data_header/start) + xs:time($dur)"></xsl:value-of>
            </xsl:element>
</xsl:template>

Thanks,

mhkay · November 30th, 2009, 07:30 PM

Neither your XML nor your XSLT is well-formed, which doesn't create a very favourable impression. When I make the obvious corrections, and run with Saxon, I get a different error from yours:

XPTY0004: Arithmetic operator is not defined for arguments of types (xs:dateTime, xs:time)

I thought we had already explained to you that you need to convert the time to a duration by subtracting xs:time('00:00:00'). So I changed the expression to

Code:

<xsl:value-of select="xs:dateTime(ancestor-or-self::node()/mydatacollection/data_header/start) + (xs:time($dur) - xs:time('00:00:00'))">

and it now runs correctly. I can't explain the error you reported - check that you are using the latest version of your XSLT processor and if it still fails, raise the problem with the vendor.