Class: Fuzzy

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

Class Method Summary collapse

Class Method Details

.assign_weights(index, regexp) ⇒ Object

recursive function to assign weight to string once there is match, removes one character from the reg exp and repeat



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# File 'lib/fuzzy_ruby.rb', line 48

def self.assign_weights(index, regexp)
  weight = @strings[index] =~ regexp
  if weight == nil
    return
  end
  @weights[index] += weight
  if !done(index)
    @strings[index] = @strings[index][weight+1..@strings[index].length]
    assign_weights(index, /#{regexp.source[5..regexp.source.length]}/)
  end
end

.build_regexp(string) ⇒ Object

build the regular expression



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# File 'lib/fuzzy_ruby.rb', line 38

def self.build_regexp(string)
  regexp = ""
  string.each_char do |c|
    regexp << "(\w*)#{c}"
  end
  regexp << "(\w*)"
end

.done(index) ⇒ Object 



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# File 'lib/fuzzy_ruby.rb', line 60

def self.done(index)
  @strings[index] == nil || @weights[index] == -1 ? true : false
end

.find(strings, input) ⇒ Object 



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# File 'lib/fuzzy_ruby.rb', line 3

def self.find(strings, input)
  # array to store weights of each string
  @weights = Array.new(strings.length, -1)

  # array to store each string
  @strings = strings.dup

  # array to return
  ret = Array.new

  # build regular expression
  regexp = /#{build_regexp(input)}/

  # for each string, calculate weight
  @strings.each_index do |i|
    assign_weights(i, regexp)
  end

  # delete string if there is no match
  @weights.each_index do |i|
    if @weights[i] == -1
      @weights.delete_at(i)
      strings.delete_at(i)
    end
  end

  # return array of strings with best match (least weight)
  @weights.map.with_index.sort_by(&:first).map(&:last).each do |index|
    ret.push strings[index]
  end

  return ret
end