SOURCE CODE: Uize.Templates.Text.Tables.Histogram (view docs)

/*______________
|       ______  |   U I Z E    J A V A S C R I P T    F R A M E W O R K
|     /      /  |   ---------------------------------------------------
|    /    O /   |    MODULE : Uize.Templates.Text.Tables.Histogram Package
|   /    / /    |
|  /    / /  /| |    ONLINE : http://www.uize.com
| /____/ /__/_| | COPYRIGHT : (c)2014-2016 UIZE
|          /___ |   LICENSE : Available under MIT License or GNU General Public License
|_______________|             http://www.uize.com/license.html
*/

/* Module Meta Data
  type: Package
  importance: 1
  codeCompleteness: 100
  docCompleteness: 4
*/

/*?
  Introduction
    The =Uize.Templates.Text.Tables.Histogram= module is a JavaScript Template module, used for generating a text-based histogram table that can be used when outputting to logs, consoles, terminals, etc.

    *DEVELOPERS:* `Chris van Rensburg`
*/

Uize.module ({
  name:'Uize.Templates.Text.Tables.Histogram',
  required:[
    'Uize.Templates.Text.Table',
    'Uize.Templates.Text.ProgressBar',
    'Uize.Data.Util',
    'Uize.Array.Util'
  ],
  builder:function () {
    'use strict';

    return Uize.package ({
      process:function (_input) {
        var
          _occurrencesByValue = _input.occurrencesByValue,
          _columnTitles = _input.columnTitles,
          _values = Uize.keys (_occurrencesByValue),
          _minValue = Uize.min (_values),
          _maxValue = Uize.max (_values),
          _maxBuckets = Uize.toNumber (_input.maxBuckets,Infinity),
          _rows
        ;
        if (_maxBuckets > _values.length) {
          _rows = Uize.map (
            _values.sort (function (_valueA,_valueB) {return _valueA - _valueB}),
            function (_value) {
              var _occurrencesForValue = _occurrencesByValue [_value];
              return [_value,_occurrencesForValue,_value * _occurrencesForValue];
            }
          );
        } else {
          var _bucketSize = (_maxValue - _minValue + 1) / _maxBuckets;
          _rows = Uize.map (
            _maxBuckets,
            function (_value,_bucketNo) {
              return [
                Math.floor (_minValue + _bucketNo * _bucketSize) +
                '-' +
                (Math.floor (_minValue + (_bucketNo + 1) * _bucketSize) - 1),
                0,
                0
              ];
            }
          );
          Uize.forEach (
            _occurrencesByValue,
            function (_occurrencesForValue,_value) {
              var _row = _rows [Math.floor ((_value - _minValue) / _bucketSize)];
              _row [1] += _occurrencesForValue;
              _row [2] += _occurrencesForValue * _value;
            }
          );
        }

        var
          _totals = Uize.Data.Util.getColumn (_rows,2),
          _maxOccurrences = Uize.max (Uize.Data.Util.getColumn (_rows,1)),
          _maxTotals = Uize.max (_totals),
          _trackLength = Uize.constrain (_maxOccurrences,20,50)
        ;

        function _barFormatter (_max) {
          return function (_value) {
            return (
              _value != undefined
                ? (
                  _value +
                  (
                    Uize.isNumber (_value)
                      ? (
                        ' ' +
                        Uize.Templates.Text.ProgressBar.process ({
                          trackLength:_trackLength,
                          endsChar:'',
                          fullHeadChar:'',
                          progress:_value / _max
                        })
                      )
                      : ''
                  )
                )
                : ''
            );
          }
        }

        return Uize.Templates.Text.Table.process ({
          title:_input.title,
          columns:[
            {title:_columnTitles.count},
            {
              title:_columnTitles.occurrences,
              align:'right',
              formatter:_barFormatter (_maxOccurrences)
            },
            {
              title:_columnTitles.total,
              align:'right',
              formatter:_barFormatter (_maxTotals)
            }
          ],
          rows:_rows.concat ([
            [
              'All (' + _minValue + '-' + _maxValue + ')',
              undefined,
              Uize.Array.Util.sum (_totals) + ''
            ]
          ])
        });
      }
    });
  }
});