Class: Daru::MultiIndex

Inherits:
Index show all
Defined in:
lib/daru/index/multi_index.rb

Overview

rubocop:disable Metrics/ClassLength

Instance Attribute Summary collapse

Attributes inherited from Index

#name, #relation_hash

Class Method Summary collapse

Instance Method Summary collapse

Methods inherited from Index

__new__, #_dump, _load, coerce, inherited, #is_values, new, #slice, #sort, #subset_slice

Constructor Details

#initialize(opts = {}) ⇒ MultiIndex

names and levels should be of same size. If size of Array name is less or greater than size of array levels then it raises SizeError. If user don’t want to put name for particular level then user must put empty string in that index of Array name. For example there is multi_index of 3 levels and user don’t want to name level 0, then do mulit_index.name = [”, ‘level1_name1’, ‘level2_name’]

Examples:


# set the name during initialization

mi = Daru::MultiIndex.new(
    levels: [[:a,:b,:c], [:one, :two]],
    labels: [[0,0,1,1,2,2], [0,1,0,1,0,1]], name: ['s1', 's2'])

# =>
# <Daru::MultiIndex(6x2)>
#   s1  s2
#    a one
#      two
#    b one
#      two
#    c one
#      two

# set new name

mi.name = ['k1', 'k2']
=> ["k1", "k2"]

mi
=>
#   #<Daru::MultiIndex(6x2)>
#   k1  k2
#    a one
#      two
#    b one
#      two
#    c one
#      two

# access the name

mi.name
=> ["k1", "k2"]

# If you don't want to name level 0

mi.name = ['', 'k2']
=> ["", "k2"]

mi
=>
#<Daru::MultiIndex(6x2)>
#       k2
#    a one
#      two
#    b one
#      two
#    c one
#      two

Raises:

  • (ArgumentError) 


79
80
81
82
83
84
85
86
87
88
89
90
 
# File 'lib/daru/index/multi_index.rb', line 79

def initialize opts={}
  labels = opts[:labels]
  levels = opts[:levels]

  raise ArgumentError, 'Must specify both labels and levels' unless labels && levels
  raise ArgumentError, 'Labels and levels should be same size' if labels.size != levels.size
  raise ArgumentError, 'Incorrect labels and levels' if incorrect_fields?(labels, levels)

  @labels = labels
  @levels = levels.map { |e| e.map.with_index.to_h }
  self.name = opts[:name] unless opts[:name].nil?
end

Instance Attribute Details

#labels ⇒ Object (readonly)

Returns the value of attribute labels.



11
12
13
 
# File 'lib/daru/index/multi_index.rb', line 11

def labels
  @labels
end

Class Method Details

.from_arrays(arrays) ⇒ Object 



105
106
107
108
109
110
111
112
113
114
 
# File 'lib/daru/index/multi_index.rb', line 105

def self.from_arrays arrays
  levels = arrays.map { |e| e.uniq.sort_by(&:to_s) }

  labels = arrays.each_with_index.map do |arry, level_index|
    level = levels[level_index]
    arry.map { |lvl| level.index(lvl) }
  end

  MultiIndex.new labels: labels, levels: levels
end

.from_tuples(tuples) ⇒ Object 



116
117
118
 
# File 'lib/daru/index/multi_index.rb', line 116

def self.from_tuples tuples
  from_arrays tuples.transpose
end

.try_from_tuples(tuples) ⇒ Object 



120
121
122
123
124
125
126
 
# File 'lib/daru/index/multi_index.rb', line 120

def self.try_from_tuples tuples
  if tuples.respond_to?(:first) && tuples.first.is_a?(Array)
    from_tuples(tuples)
  else
    nil
  end
end

Instance Method Details

#&(other) ⇒ Object 



299
300
301
 
# File 'lib/daru/index/multi_index.rb', line 299

def & other
  MultiIndex.from_tuples(to_a & other.to_a)
end

#==(other) ⇒ Object 



322
323
324
325
326
 
# File 'lib/daru/index/multi_index.rb', line 322

def == other
  self.class == other.class  &&
    labels   == other.labels &&
    levels   == other.levels
end

#[](*key) ⇒ Object 



128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
 
# File 'lib/daru/index/multi_index.rb', line 128

def [] *key
  key.flatten!
  case
  when key[0].is_a?(Range)
    retrieve_from_range(key[0])
  when key[0].is_a?(Integer) && key.size == 1
    try_retrieve_from_integer(key[0])
  else
    begin
      retrieve_from_tuples key
    rescue NoMethodError
      raise IndexError, "Specified index #{key.inspect} do not exist"
    end
  end
end

#add(*indexes) ⇒ Object 



198
199
200
 
# File 'lib/daru/index/multi_index.rb', line 198

def add *indexes
  Daru::MultiIndex.from_tuples to_a << indexes
end

#at(*positions) ⇒ object

Takes positional values and returns subset of the self

capturing the indexes at mentioned positions

Examples:

idx = Daru::MultiIndex.from_tuples [[:a, :one], [:a, :two], [:b, :one], [:b, :two]]
idx.at 0, 1
# => #<Daru::MultiIndex(2x2)>
#   a one
#     two

Parameters:

  • positions (Array<Integer>) —

    positional values

Returns:

  • (object) —

    index object



188
189
190
191
192
193
194
195
196
 
# File 'lib/daru/index/multi_index.rb', line 188

def at *positions
  positions = preprocess_positions(*positions)
  validate_positions(*positions)
  if positions.is_a? Integer
    key(positions)
  else
    Daru::MultiIndex.from_tuples positions.map(&method(:key))
  end
end

#coerce_index ⇒ Object 



250
251
252
253
254
255
256
257
258
259
260
261
262
 
# File 'lib/daru/index/multi_index.rb', line 250

def coerce_index
  if @levels.size == 1
    elements = to_a.flatten

    if elements.uniq.length == elements.length
      Daru::Index.new(elements)
    else
      Daru::CategoricalIndex.new(elements)
    end
  else
    self
  end
end

#conform(input_indexes) ⇒ Object

Provide a MultiIndex for sub vector produced

Parameters:

  • input_indexes (Array) —

    the input by user to index the vector

Returns:

  • (Object) —

    the MultiIndex object for sub vector produced



350
351
352
353
 
# File 'lib/daru/index/multi_index.rb', line 350

def conform input_indexes
  return self if input_indexes[0].is_a? Range
  drop_left_level input_indexes.size
end

#drop_left_level(by = 1) ⇒ Object 



291
292
293
 
# File 'lib/daru/index/multi_index.rb', line 291

def drop_left_level by=1
  MultiIndex.from_arrays to_a.transpose[by..-1]
end

#dup ⇒ Object 



287
288
289
 
# File 'lib/daru/index/multi_index.rb', line 287

def dup
  MultiIndex.new levels: levels.dup, labels: labels.dup, name: (@name.nil? ? nil : @name.dup)
end

#each(&block) ⇒ Object 



3
4
5
 
# File 'lib/daru/index/multi_index.rb', line 3

def each(&block)
  to_a.each(&block)
end

#empty? ⇒ Boolean

Returns:

  • (Boolean) 


303
304
305
 
# File 'lib/daru/index/multi_index.rb', line 303

def empty?
  @labels.flatten.empty? && @levels.all?(&:empty?)
end

#include?(tuple) ⇒ Boolean

Returns:

  • (Boolean) 


307
308
309
310
311
312
 
# File 'lib/daru/index/multi_index.rb', line 307

def include? tuple
  return false unless tuple.is_a? Enumerable
  @labels[0...tuple.flatten.size]
    .transpose
    .include?(tuple.flatten.each_with_index.map { |e, i| @levels[i][e] })
end

#inspect(threshold = 20) ⇒ Object 



336
337
338
339
 
# File 'lib/daru/index/multi_index.rb', line 336

def inspect threshold=20
  "#<Daru::MultiIndex(#{size}x#{width})>\n" +
    Formatters::Table.format([], headers: @name, row_headers: sparse_tuples, threshold: threshold)
end

#key(index) ⇒ Object

Raises:

  • (ArgumentError) 


279
280
281
282
283
284
285
 
# File 'lib/daru/index/multi_index.rb', line 279

def key index
  raise ArgumentError, "Key #{index} is too large" if index >= @labels[0].size

  @labels
    .each_with_index
    .map { |label, i| @levels[i].keys[label[index]] }
end

#levels ⇒ Object 



13
14
15
 
# File 'lib/daru/index/multi_index.rb', line 13

def levels
  @levels.map(&:keys)
end

#map(&block) ⇒ Object 



7
8
9
 
# File 'lib/daru/index/multi_index.rb', line 7

def map(&block)
  to_a.map(&block)
end

#name=(names) ⇒ Object 



92
93
94
95
 
# File 'lib/daru/index/multi_index.rb', line 92

def name=(names)
  validate_name names, @labels
  @name = names
end

#pos(*indexes) ⇒ Object

Note:

If the arugent is both a valid index and a valid position, it will treated as valid index

Returns positions given indexes or positions

Examples:

idx = Daru::MultiIndex.from_tuples [[:a, :one], [:a, :two], [:b, :one], [:b, :two]]
idx.pos :a
# => [0, 1]

Parameters:

  • indexes (Array<object>) —

    indexes or positions



160
161
162
163
164
165
166
167
168
 
# File 'lib/daru/index/multi_index.rb', line 160

def pos *indexes
  if indexes.first.is_a? Integer
    return indexes.first if indexes.size == 1
    return indexes
  end
  res = self[indexes]
  return res if res.is_a? Integer
  res.map { |i| self[i] }
end

#remove_layer(layer_index) ⇒ Object 



242
243
244
245
246
247
248
 
# File 'lib/daru/index/multi_index.rb', line 242

def remove_layer layer_index
  @levels.delete_at(layer_index)
  @labels.delete_at(layer_index)
  @name.delete_at(layer_index) unless @name.nil?

  coerce_index
end

#reorder(new_order) ⇒ Object 



202
203
204
205
 
# File 'lib/daru/index/multi_index.rb', line 202

def reorder(new_order)
  from = to_a
  self.class.from_tuples(new_order.map { |i| from[i] })
end

#size ⇒ Object 



314
315
316
 
# File 'lib/daru/index/multi_index.rb', line 314

def size
  @labels[0].size
end

#sparse_tuples ⇒ Object

Return tuples with nils in place of repeating values, like this:

:a , :bar, :one
nil, nil , :two
nil, :foo, :one


361
362
363
364
365
366
367
 
# File 'lib/daru/index/multi_index.rb', line 361

def sparse_tuples
  tuples = to_a
  [tuples.first] + each_cons(2).map { |prev, cur|
    left = cur.zip(prev).drop_while { |c, p| c == p }
    [nil] * (cur.size - left.size) + left.map(&:first)
  }
end

#subset(*indexes) ⇒ Object 



170
171
172
173
174
175
176
 
# File 'lib/daru/index/multi_index.rb', line 170

def subset *indexes
  if indexes.first.is_a? Integer
    MultiIndex.from_tuples(indexes.map { |index| key(index) })
  else
    self[indexes].conform indexes
  end
end

#to_a ⇒ Object 



328
329
330
 
# File 'lib/daru/index/multi_index.rb', line 328

def to_a
  (0...size).map { |e| key(e) }
end

#to_html ⇒ Object 



341
342
343
344
 
# File 'lib/daru/index/multi_index.rb', line 341

def to_html
  path = File.expand_path('../../iruby/templates/multi_index.html.erb', __FILE__)
  ERB.new(File.read(path).strip).result(binding)
end

#try_retrieve_from_integer(int) ⇒ Object 



207
208
209
 
# File 'lib/daru/index/multi_index.rb', line 207

def try_retrieve_from_integer int
  @levels[0].key?(int) ? retrieve_from_tuples([int]) : int
end

#valid?(*indexes) ⇒ Boolean

Returns:

  • (Boolean) 


144
145
146
147
148
149
150
 
# File 'lib/daru/index/multi_index.rb', line 144

def valid? *indexes
  # FIXME: This is perhaps not a good method
  pos(*indexes)
  return true
rescue IndexError
  return false
end

#values ⇒ Object 



332
333
334
 
# File 'lib/daru/index/multi_index.rb', line 332

def values
  Array.new(size) { |i| i }
end

#width ⇒ Object 



318
319
320
 
# File 'lib/daru/index/multi_index.rb', line 318

def width
  @levels.size
end

#|(other) ⇒ Object 



295
296
297
 
# File 'lib/daru/index/multi_index.rb', line 295

def | other
  MultiIndex.from_tuples(to_a | other.to_a)
end