lispとrubyとpythonと その3 リスト処理 （ruby）

ずいぶん空いた。
・まず12時前にはかえれない。
・週１〜3日は朝の4時とかまで働く。
・土日も結構仕事（家でできるけど）
って状態はどうなんでしょ？？
つかもーイヤになってきた。

愚痴はともかく。
その3はリスト処理がメイン。
やることが多いのでこれだけで一回分にした。
↓に書いたRubyのサンプルはだいぶ前に書いたからもう内容あんまり覚えてない・・・。

#! /usr/bin/ruby -Ku

#lambda式の追記
#1.9なのでこうかける
f0 = ->a,b{puts a + b}

#呼び出しはこんな感じ
#昔と同じ
f0.call("a","b")
f0["a","b"]

#こう書けるようになった
#しかし微妙
f0.("a","b")

#rubyのlambdaとProcの違いってなんなんだろ？？

#ブロックをとる関数
def f_with_block(a,&body)
  #受け取るとProcになってる
  puts body
  body.("f_with_block:" + a)
end

f_with_block "test" do |s|
  puts s
end 

#配列
arr = ["abc","def","ghi","jkl"]

#取得
puts arr
puts arr[0]
puts arr[1]

#回す
arr.each do |a|
  puts a
end

arr.each_with_index do |a,i|
  puts i.to_s + ":" + a
end

#配列のメソッドはここ
#http://doc.loveruby.net/refm/api/view/class/Array
#気になったものだけサンプルを書く

arr1 = [1,2,3]
arr2 = [2,3,4]

#積集合
puts (arr1 & arr2).to_s

#和集合
puts (arr1 | arr2).to_s

#差集合
puts (arr1 - arr2).to_s

#choice
#配列の要素をランダムに選ぶメソッド
puts arr1.choice()

#map(collect)
puts arr1.to_s

arr1.map do |e|
  e + 1
end

puts arr1.to_s

puts "------------------------------"
#combination
#これ便利かも
arr1 = [1,2,3,4]
arr1.combination 2 do |e|
  puts e.to_s
end
puts "------------------------------"
#permutation
arr1 = [1,2,3,4]
arr1.permutation 2 do |e|
  puts e.to_s
end


#cycle
arr1 = [1,2,3]
puts arr1.zip(["a","b"].cycle).to_a.to_s

#すぐに評価されちゃうから使えない
#元の配列をクリアすれば止まる
arr1 = [1,2,3]
i = 0
arr1.cycle do |e|
  puts e
  arr1.clear if i > 10
  i = i + 1
end

#flatten
#これもイイなー
arr1 = [1,2,[3,[4,5],6],7,[8,9
puts arr1.flatten.to_s

#pack...あとで調べる

#product
arr1 = [1,2,3]
puts arr1.product(["a","b","c"],[:a,:b,:c]).to_s

#transpose
#行列入れ替え
#これもいい。
arr1 = 1,2,3,4],
        ["data1","data2","data3","data4"
puts arr1.transpose.to_s

#uniq
#重複の削除
arr1 = [1,2,2,3,4,5,3,1]
puts arr1.uniq.to_s
puts "------------------------------"

#zip
arr1 = [1,2,3]
puts arr1.zip(["a","b","c","d"],[:a,:b]).to_a.to_s

#Enumerable

#all?
arr1 = [2,4,6]
puts arr1.all?{|e| e % 2 == 0 }

#any?
arr1 = [1,2,3,5]
puts arr1.any?{|e| e % 2 == 0 }

#count
arr1 = [1,2,3,4,5]
#countするとEnumerable::Enumeratorが戻って来てしまう
#よくわからん
puts "count:" + arr1.count.to_s
puts "size:" + arr1.size.to_s

#これならとれてる
#arr1の中の2の要素数を表示
puts "count:" + arr1.count(2).to_s
#arr1で偶数の要素数を表示
puts "count:" + arr1.count{|e| e % 2 == 0}.to_s

#cycle
arr1 = [1,2,3]
puts arr1.zip(["a","b"].cycle).to_a.to_s

#find detect 
#最初に条件を満たしたものをかえす
arr1 = [1,2,3,4,5]
puts arr1.find{|e| e > 4}.to_s

#drop_while
arr1 = [1,2,3,4,5]
puts arr1.drop_while{|e| e < 3}.to_s

#each_cons enum_cons
arr1 = [1,2,3,4,5]
arr1.each_cons 3 {|e| puts e.to_s}

#each_slice enum_slice
arr1 = [1,2,3,4,5]
arr1.each_slice 2 {|e| puts e.to_s}

#find_all select
arr1 = [1,2,3,4,5]
puts arr1.find_all{|e|e % 2 ==0}.to_s

#find_index
arr1 = [1,2,3,4,5]
puts arr1.find_index{|e|e % 2 ==0}

#first
arr1 = [1,2,3,4,5]
puts arr1.first.to_s
puts arr1.first(2).to_s

#grep
arr1 = ["aaa","bbb","ccc"]
puts arr1.grep(/^[bc]*$/).to_s

#group_by
tbl = "taro","python"],
       ["taro","ruby"],
       ["jiro","commonlisp"],
       ["jiro","pyhon"],
       ["jiro","sheme"],
       ["hanako","c"],
       ["hanako","ruby"],
       ["youko","python"],
       ["youko","commonlisp"

puts tbl.group_by{|e|e[0]}.to_s

#member? include?
arr1 = [1,2,3,4,5]
puts arr1.member?(2).to_s

#inject reduce
arr1 = [1,2,3]
puts arr1.reduce([]) {|a,e|
  a + [e * 2]
}.to_s

#max
arr1 = [1,2,3]
puts arr1.max

#max_by
arr1 = [1,2,3]
puts arr1.max_by{|e|
  e * -1
}.to_s

#min
arr1 = [1,2,3]
puts arr1.min

#min_by
arr1 = [1,2,3]
puts arr1.min_by{|e|
  e * -1
}.to_s

#minmax
arr1 = [1,2,3]
puts arr1.minmax.to_s

#none?
arr1 = [1,3,5]
puts arr1.none?{|e| e % 2 == 0}

#one?
arr1 = [1,2,3,5]
puts arr1.one?{|e| e % 2 == 0}

#partition
arr1 = [1,2,3,4,5]
puts arr1.partition{|e| e % 2 == 0}.to_s

#reject
arr1 = [1,2,3,4,5]
puts arr1.reject{|e|e % 2 ==0}.to_s

#sort
arr1 = [2,3,1,4,5]
puts arr1.sort.to_s

#sort_by

#take
arr1 = [1,2,3]
puts arr1.cycle.take(10).to_s

#take_while
arr1 = [1,2,3]
puts arr1.cycle.each_with_index.take_while{|e|
  e[1] > 10}

#zip
arr1 = ["a","b","c","d"]
puts arr1.zip([1,2].cycle,[:a,:b,:c].cycle).to_a.to_s

#arrayが返ったり、Enumerable::Enumerator1が返ったり。
#どういうとき何がかえるのか正直分かってない
arr1 = [1,2,3]
puts arr1.cycle.take(10).class.name
puts arr1.zip([1,2].cycle,[:a,:b,:c].cycle).class.name