lib/mint/generator/complex_number_arithmetic.rb

   1 # -*- coding: nil -*-
   2
   3 module Mint::Generator
   4
   5   #
   6   # 複素数の問題を生成するジェネレータ
   7   #
   8   # オプション ::
   9   #               以下のオプションが使用出来る
  10   #               [_term_number_] 生成する項の数 (ex. 2)
  11   #               [_operators_] 使用する演算子 (ex. %w[ * / ])
  12   #               [_min_] 各項の最小値 (ex. 0)
  13   #               [_max_] 各項の最大値 (ex. 100)
  14   #               [_fractional_mode_] 真なら分数形式の項を生成する (ex. false)
  15   #
  16   class ComplexNumberArithmetic < Arithmetic
  17
  18     private
  19
  20     def generate_problem
  21       defaults = {
  22         :min => 1, :max => 9,
  23         :fractional_mode => false,
  24         :operators => %w[ * / ]
  25       }
  26       if options[:fractional_mode]
  27         @options[:operators] = %w[ + - ]
  28       end
  29       do_generate(defaults)
  30     end
  31
  32     def operand
  33       result =
  34         if options[:fractional_mode]
  35           create_fractional_complex_number
  36         else
  37           "(#{create_complex_number})"
  38         end
  39       return "#{result}^2"if options[:term_number] == 1
  40       if last_operator == '/'
  41         return conjugate_complex(last_operand)
  42       end
  43       result
  44     end
  45
  46     def create_complex_number
  47       real_part = create_integer(options[:min], options[:max], false)
  48       imaginary_part =  create_integer(options[:min], options[:max], false)
  49       return (2 + rand(8)).to_s if [real_part, imaginary_part].include? 0
  50       operator =  %w[ + - ].sample
  51       "#{real_part} #{operator} #{imaginary_part.to_s.sub('1', '')}%i"
  52     end
  53
  54     def create_fractional_complex_number
  55       numerator_part = 1 + rand(9)
  56       denominator_part = create_complex_number
  57       "#{numerator_part} / (#{denominator_part})"
  58     end
  59
  60     def conjugate_complex(expression)
  61       a, op, b = *expression.split
  62       op = op == '+' ? '-' : '+'
  63       "#{a} #{op} #{b}"
  64     end
  65   end
  66 end
  67