MarkLogic 10 Product Documentationcts:median
cts:median( $arg as xs:double* ) as xs:double?
Summary
Returns a frequency-weighted median of a sequence.
This function works like math:median except each item in the
sequence is repeated cts:frequency times before calculating
the median. If $arg is the empty sequence, the function returns the empty
sequence.
| Parameters | |
|---|---|
| arg | The sequence of values. The values should be the result of a lexicon lookup. |
Usage Notes
This function is designed to take a sequence of values returned
by a lexicon function (for example, cts:element-values); if you
input non-lexicon values, the result will be the empty sequence.
Example
xquery version "1.0-ml";
(:
This query assumes an element range index of type 'int'
is configured for the 'int' element in the database. It
generates some sample data and then performs the aggregation
in a separate transaction.
:)
for $x in 1 to 10
return
xdmp:document-insert(fn:concat($x, ".xml"),
<my-element>{
for $y in 1 to $x
return <int>{$x}</int>
}</my-element>);
cts:median(cts:element-values(xs:QName("int"), (),
("type=int", "item-frequency"))),
cts:median(cts:element-values(xs:QName("int"), (),
("type=int", "fragment-frequency")))
=>
7
5.5