XSLT 2.0 and XPath 2.0 Programmer's Reference, 4th Edition (344 page)
Read XSLT 2.0 and XPath 2.0 Programmer's Reference, 4th Edition Online
Authors: Michael Kay
Here are some examples:
| Expression | Result |
| xs:dayTimeDuration(“P10D”) div xs:dayTimeDuration(“PT6H”) | 40 |
| xs:dayTimeDuration(“-P1D”) div xs:dayTimeDuration(“PT1S”) | −86400 |
| xs:yearMonthDuration(“P1M”) div xs:yearMonthDuration(“P1Y”) | 0.083333333… |
This operation provides the easiest way to convert a duration into a number of months, days, or seconds. To convert an
xs:dayTimeDuration
to seconds, for example, just divide it by
xs:dayTimeDuration(“PT1S”)
. This is useful when you need to perform calculations that are not directly supported by the operations available on durations. Examples include:
- Dividing a distance by a duration to obtain an average speed.
- Multiplying the number of hours worked by the hourly rate to obtain the amount of money due.
- Determining the day of the week for a given date.
The following code illustrates how to display the day of the week, supplied in the variable
$date
:
(“Sunday”, “Monday”, “Tuesday”, “Wednesday”, “Thursday”, “Friday”, “Saturday”)
[1 + (($date - xs:date(“1901-01-06”)) div xs:dayTimeDuration(“P1D”) mod 7)]
In XSLT 2.0, however, you can display the day of the week using the
format-date()
function, described in Chapter 13.
Value Comparisons
XPath 2.0 has introduced a completely new set of operators for comparing single atomic values. These are shown in the table below.
| Operator | Meaning |
| eq | equals |
| ne | not equals |
| lt | less than |
| le | less than or equal to |
| gt | greater than |
| ge | greater than or equal to |
These were introduced primarily because they have much cleaner and more predictable behavior than the XPath 1.0 operators
=
,!=,<,<=,>, and>=. The XPath 1.0 operators are still available, and they are described later in this chapter under the heading
General Comparisons
on page 588.
