Re: Doing Math on Durations and Creating dayTimeDurati

> A lot of people miss this one. By providing a convenient operator for this common operation,
> we ensured that people searching the function library wouldn't find it...
>
> Michael Kay
> Saxonica

The reason is the "op:some-descriptiveName"  convention created
totally unreadable document that requires a lot of effort to
understand what each name actually means:

     10.8 Arithmetic Operators on Durations, Dates and Times
        10.8.1 op:subtract-dateTimes
        10.8.2 op:subtract-dates
        10.8.3 op:subtract-times
        10.8.4 op:add-yearMonthDuration-to-dateTime
        10.8.5 op:add-dayTimeDuration-to-dateTime
        10.8.6 op:subtract-yearMonthDuration-from-dateTime
        10.8.7 op:subtract-dayTimeDuration-from-dateTime
        10.8.8 op:add-yearMonthDuration-to-date
        10.8.9 op:add-dayTimeDuration-to-date
        10.8.10 op:subtract-yearMonthDuration-from-date
        10.8.11 op:subtract-dayTimeDuration-from-date
        10.8.12 op:add-dayTimeDuration-to-time
        10.8.13 op:subtract-dayTimeDuration-from-time

In the above (TOC of the W3C XPath 2.0 F & O standard), the
subtraction  " - " of twodateTime values is difficult to find and
understand even though it is the first in the list and must be the
easiest to see.

I think that the above is a very effective encryption of the contents
of the document.

On Thu, Oct 6, 2016 at 7:02 AM, Michael Kay mike@xxxxxxxxxxxx
<xsl-list-service@xxxxxxxxxxxxxxxxxxxxxx> wrote:
> A lot of people miss this one. By providing a convenient operator for this common operation, we ensured that people searching the function library wouldn't find it...
>
> Michael Kay
> Saxonica
>
>> On 6 Oct 2016, at 13:37, Eliot Kimber ekimber@xxxxxxxxxxxx <xsl-list-service@xxxxxxxxxxxxxxxxxxxxxx> wrote:
>>
>> I think that's what I missed: I didn't realize you could do arithmetic
>> that directly.
>>
>> I'll try it.
>>
>> Cheers,
>>
>> Eliot
>> --
>> Eliot Kimber
>> http://contrext.com
>>
>>
>>
>>
>>
>>
>>
>> On 10/6/16, 12:24 PM, "Jirka Kosek jirka@xxxxxxxx"
>> <xsl-list-service@xxxxxxxxxxxxxxxxxxxxxx> wrote:
>>
>>> On Thu, Oct 6, 2016, at 11:40, Eliot Kimber ekimber@xxxxxxxxxxxx wrote:
>>>> I'm using XSLT to extract timing information from logs in order to
>>>> determine the duration of actions. Each log item has a time stamp in the
>>>> usual format (2016-10-05T15:52:17.525:+0200).
>>>
>>> And why are you simply not just subtracting two dateTimes, something
>>> like:
>>>
>>> xs:dateTime("2015-01-01T12:00:00Z") -
>>> xs:dateTime("2014-07-10T12:00:00Z")
>>>
>>> This will give you back duration. Or perhaps I have misunderstood...
>>>
>>> Jirka
>>>
>>> --
>>> ------------------------------------------------------------------
>>> Jirka Kosek      e-mail: jirka@xxxxxxxx      http://xmlguru.cz
>>> ------------------------------------------------------------------
>>>      Professional XML consulting and training services
>>> DocBook customization, custom XSLT/XSL-FO document processing
>>> ------------------------------------------------------------------
>>> OASIS DocBook TC member, W3C Invited Expert, ISO JTC1/SC34 member
>>> ------------------------------------------------------------------
>>>
>>>
>>
> 



-- 
Cheers,
Dimitre Novatchev
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