require "csv"

module Uranai
  class Data
    def initialize(csv)
      @data = CSV.read(csv).map { |arr| arr.map(&:to_f) }.transpose
    end

    def column_size
      data.length
    end

    def row_size
      data.transpose.length
    end
    alias :training_example_size :row_size

    def feature_size
      column_size - 1
    end

    def x
      data[0...column_size-1].insert(0, [1] * row_size)
    end

    def matrix_x
      Matrix.columns(x)
    end

    def y
      [data[-1]]
    end

    def matrix_y
      Matrix.columns(y)
    end

    private

    attr_reader :data
  end
end