Class: JsDuck::Columns

Inherits:
Object
  • Object
show all
Defined in:
lib/jsduck/columns.rb

Overview

Splits array of items with subitems into roughly equal size groups.

Instance Method Summary collapse

Constructor Details

#initialize(subitems_field) ⇒ Columns

Initialized with the name of subitems field.



6
7
8
9
 
# File 'lib/jsduck/columns.rb', line 6

def initialize(subitems_field)
  @header_size = 3
  @subitems_field = subitems_field
end

Instance Method Details

#split(items, n) ⇒ Object

Splits the array of items into n chunks so that the sum of largest chunk is as small as possible.

This is a brute-force implementation - we just try all the combinations and choose the best one.



16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
 
# File 'lib/jsduck/columns.rb', line 16

def split(items, n)
  if n == 1
    [items]
  elsif items.length <= n
    Array.new(n) {|i| items[i] ? [items[i]] : [] }
  else
    min_max = nil
    min_arr = nil
    i = 0
    while i <= items.length-n
      i += 1
      # Try placing 1, 2, 3, ... items to first chunk.
      # Calculate the remaining chunks recursively.
      cols = [items[0,i]] + split(items[i, items.length], n-1)
      max = max_sum(cols)
      # Is this the optimal solution so far? Remember it.
      if !min_max || max < min_max
        min_max = max
        min_arr = cols
      end
    end
    min_arr
  end
end