.. _months-from-duration:

====================
months-from-duration
==================== 

The number of months in a duration

Description
~~~~~~~~~~~
The fn:months-from-duration function calculates the months component of a 
normalized xs:duration value, as an integer between -11 and 11 inclusive. This 
is not necessarily the same as the integer that appears before the M in the 
value. For example, if the duration is P18M, the function returns 6 rather than 
18. This is because 12 of those months are considered to be one year, and the 
normalized value is therefore P1Y6M.

For a function that returns the total number of months as a decimal number, see 
functx:total-months-from-duration.

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   * - **Parameters**
     - **Description**
   * - arg:numeric()
     - 

Examples
~~~~~~~~
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   * - **XPath**
     - **Results**
   * - months-from-duration(xs:yearMonthDuration('P3M'))
     - 3
   * - months-from-duration(xs:yearMonthDuration('-P18M'))
     - -6
   * - months-from-duration(xs:yearMonthDuration('P1Y'))
     - 0
   * - months-from-duration(xs:yearMonthDuration('P12M'))
     - 0

See Also
~~~~~~~~

.. toctree::
   :titlesonly:
   :glob:

* :ref:`functx_total-months-from-duration`.