Median of Field Entries

Here is a JavaScript function getMedian that takes (1) a table dbid, (2) a query string, and (3) a fid of a numeric field and returns a promise that resolves to the median:

function getMedian(dbid, query, fid) {
  return Promise.resolve(
    $.get(dbid, {
      act: "API_DoQuery",
      query,
      clist: fid,
      fmt: "structured"
    })
  ).then(function(xml) {
    var data = $('qdbapi table records record f[id=${fid}]', xml).map(function() {
      return parseFloat($(this).text());
    });
    data.sort((x, y) => x - y);
    var ilm = Math.floor((data.length - 1) / 2);
    var ihm = Math.ceil((data.length - 1) / 2);
    var median = (data[ilm] + data[ihm]) / 2;
    return median;
  })
}

You call it like this:

var dbid = "bnxssrg9s";
var dbidTable = "bnzd357bm";
var apptoken = "cnurzq5cgchgjgdsdiup6cgkq6ct";
$.ajaxSetup({data: {apptoken}}); 
var query = "{3.GT.0}";
var fid = "8"; 
getMedian(dbidTable, query, fid)
  .then(function(median) {
    console.log(median);
  });

When called on a sample application with this numeric data:

0: 60000
1: 65000
2: 70000
3: 75000
4: 85000
5: 155000
6: 160000
7: 200000

it correctly calculates the median as 80000 (average of midpoints 75000 and 85000).

The organization of this script can calculate any mean, metric or norm of a list of numeric data.

I created this hypothetical GUI interface so QuickBase developers can hardcode the most popular means, metrics and norm functions: