(:
   file:    dyn_freq_1var_1year.xq
   date:    26-July-2010
   author:  Gary Lewis
   purpose: Dynamically (ie, at run-time) generates a XQuery program which, when run, produces
            a frequency distribution for 1 specified variable in 1 specified survey year.
   usage:   Run program from the path where it is located.
   example: zorba -e year:="1984" -e var:="stabbr" -f -q dyn_freq_1var_1year.xq -o freq_1var_1year.xq -z method=text

   revision history:
   date:    27-July-2010
   author:  Gary Lewis
   revised: 1. To sort numeric codes as numbers instead of as alphanumerics.

:)

declare variable $year external;
declare variable $var external;

let $nl := "
",
    $dq := """",
    $dateTime := format-dateTime(current-dateTime(), "[D]-[MNn]-[Y] [H01]:[m01][Pn] [ZN]"),
    $tmp := text{concat(
                 "(:",$nl,
                 "   file:    freq_1var_1year.xq",$nl,
                 "   date:    ",$dateTime,$nl,
                 "   author:  Program created by dyn_freq_1var_1year.xq",$nl,
                 "   purpose: Outputs a frequency distribution for the variable ",$var," in survey year ",$year,".",$nl,
                 "   usage:   Run this program from its path location.",$nl,
                 "   example: zorba -f -q freq_1var_1year.xq -o freq_",$var,"_",$year,".xml -z indent=yes",$nl,
                 ":)",$nl,"",$nl,
                 "<results year=",$dq,$year,$dq," var=",$dq,$var,$dq,">",$nl,
                 "{",$nl,
                 "let $x := fn:doc(",$dq,"../xml/metadata/ipedsData.xml",$dq,")/data/file[@year = ",$dq,$year,$dq,"][@type = ",$dq,"xml",$dq,"],",$nl,
                 "    $fileName := $x/@name,",$nl,
                 "    $path := $x/@path,",$nl,
                 "    $xmlFile := concat($path, $fileName)",$nl,
                 "for $i in fn:doc($xmlFile)/data/record/@",$var,$nl,
                 "let $dataType := fn:doc(",$dq,"../xml/metadata/ipedsVars_metadata.xml",$dq,")/variables/var[@name = ",$dq,$var,$dq,"]/detail[@year = ",$dq,$year,$dq,"]/@dataType,",$nl,
                 "    $label := fn:doc(",$dq,"../xml/metadata/ipedsVars_metadata_codes.xml",$dq,")/variables/var[@name = ",$dq,$var,$dq,"][@year = ",$dq,$year,$dq,"]/code[@value = $i]/@label,",$nl,
                 "    $freq := 1,",$nl,
                 "    $sortOrder := if ($dataType = ",$dq,"N",$dq,") then (if ($i = ",$dq,$dq,") then -999 else xs:integer($i)) else $i",$nl,
                 "group by $sortOrder, $label",$nl,
                 "order by $sortOrder", $nl,
                 "return <freq count=",$dq,"{sum($freq)}",$dq," code=",$dq,"{$sortOrder}",$dq," label=",$dq,"{$label}",$dq,"/>",
                 "}",$nl,
                 "</results>"
                )}
return $tmp