YearFrequency-FullText.xquery

xquery version "3.1" encoding "UTF-8";

(:~
 : A public function to return the frequency of a string.
 :
 : @author Adam Steffanick
 : @see https://www.steffanick.com/adam/
 : @version v1.0.0
 :
 : @param $parameter is a string
 : @return a sequence of record elements
 :)
declare %public function local:frequency(
  $parameter as xs:string
) as element(record)*
{
  let $results := (
    for $document in fn:collection("bp-sample")
    let $date := (
      $document//NumericPubDate/text()
      => substring(1, 4)
    )
    let $frequency := (
      ft:count($document//FullText[.//text() contains text {$parameter} using case insensitive using stemming])
    )
    group by $date
    return (
      element record {
        element date {
          $date
        },
        element frequency {
          fn:sum($frequency)
        }
      }
    )
  )
  return (
    $results
  )
};

local:frequency("jury")