Contents

# Turns a data frame into ARFF-formatted content.
module ARFF

  # Used in arff, but generally useful.
  def to_csv(include_header=true)
    value = include_header ? self.labels.map{|e| e.to_s}.join(',') + "\n" : ''
    self.items.inject(value) do |list, e|
      list << e.map {|cell| cell.to_s}.join(',') + "\n"
    end
  end

  def to_arff
    arff_header + to_csv(false)
  end
  
  protected
    def arff_attributes
      container = defined?(Dictionary) ? Dictionary.new : Hash.new
      
      self.labels.inject(container) do |list, e|
        list[e] = self.render_column(e).categories
      end
    end
    
    def arff_formatted_attributes
      self.labels.inject('') do |str, e|
        val = "{" + self.render_column(e).categories.map{|x| x.to_s}.join(',') + "}"
        str << "@attribute #{e} #{val}\n"
      end
    end
    
    def arff_relation
      self.name ? self.name.to_underscore_sym.to_s : 'unamed_relation'
    end
    
    def arff_header
      %[@relation #{arff_relation}

#{arff_formatted_attributes}
@data   
]
    end
    
    alias :arff_items :to_csv
end

Version data entries

1 entries across 1 versions & 1 rubygems

Version	Path
davidrichards-data_frame-0.0.18	lib/data_frame/arff.rb