データのまとまり

配列・ハッシュ

【開発環境】
OS：Win11（64ビット）
Ruby 3.0.1
VSCodeバージョン: 1.57.1

【配列】
ruby 3.0.1p64 (2021-04-05 revision 0fb782ee38) [x64-mingw32]

C:\Users\shyok>irb
irb(main):001:0> animals = ['dog','cat','mouse']
=> ["dog", "cat", "mouse"]
irb(main):002:0> animals[0]
=> "dog"
irb(main):003:0> animals[1]
=> "cat"

・要素の追加
irb(main):004:0> animals << 'bird'
=> ["dog", "cat", "mouse", "bird"]
irb(main):005:0>

・変更
irb(main):005:0> animals[2] = 'bird'
=> "bird"
irb(main):006:0> animals
=> ["dog", "cat", "bird", "bird"]
irb(main):007:0>

・削除
irb(main):007:0> animals.delete('bird')
=> "bird"
irb(main):008:0> animals
=> ["dog", "cat"]

・入力
irb(main):010:0> animals.insert(2,'mouse')
=> ["dog", "cat", "mouse"]
irb(main):011:0>
ruby 3.0.1p64 (2021-04-05 revision 0fb782ee38) [x64-mingw32]

【ハッシュ】
C:\Users\shyok>irb
irb(main):001:0> man = {'height' => 170,'weight' => 65 }
=> {"height"=>170, "weight"=>65}
irb(main):002:0> man['height']
=> 170
irb(main):003:0> man['weight']
=> 65
irb(main):004:0>

キーをシンボルで表すと
irb(main):004:0> wman = {:height => 160,:weight => 50}
=> {:height=>160, :weight=>50}
irb(main):005:0> wman[:height]
=> 160
irb(main):006:0> wman[:weight]
=> 50
irb(main):007:0>

データを追加する
irb(main):007:0> child = {height: 110,weight: 20}
=> {:height=>110, :weight=>20}
irb(main):008:0> child[:age] = 7
=> 7
irb(main):009:0> child
=> {:height=>110, :weight=>20, :age=>7}
irb(main):010:0>
irb(main):011:0> child.delete(:age)
=> 7
irb(main):012:0> child
=> {:height=>110, :weight=>20}
irb(main):013:0>