個人用ユーティリティGem

utils.rb

require 'utils/version'
require 'open-uri'
require 'fastimage'

module Utils
  #Pythonの配列のsliceと同等のメソッド
  #stepは省略可。leftとrightは省略する代わりにnil
  module Pyrb
    def pickup(left, right, step=nil)
      klass = self.class
      len = self.length
      unless step
	return klass.new unless !right or right != 0
	left ||= 0
	right ||= 0
	right -= 1
	self[left..right]
      else
	if step > 0
	  left ||= 0
	  right ||= len
	  left = convp(left, len)
	  right = convp(right, len)
	  right = len if right >= len
	  right -= 1
	elsif step < 0
	  left ||= len - 1
	  left = len - 1 if left >= len
	  right ||= - len - 1
	  left = convm(left, len)
	  right = convm(right, len)
	  right = - len - 1 if right < - len - 1
	  right += 1
	else
	  raise "ValueError: slice step cannot be zero"
	end
	selected = klass.new
	left.step(right, step) {|i| selected << self[i]}
	selected
      end
    end
    
    def convp(i, len)
      return i if i >= 0
      i + len
    end
    
    def convm(i, len)
      return i if i < 0
      i - len
    end
    private :convp, :convm
  end
  Array.send(:include, Pyrb)
  String.send(:include, Pyrb)  
  
  def self.imgexist?(url)
    FastImage.size(url)
  end
  
  def self.getfile(url, filename, max=0)
    count = 0
    begin
      open(filename, 'wb') do |file|
	open(url) {|data| file.write(data.read)}
      end
      true 
    rescue
      puts "ファイル入出力エラー： " + $!.message.encode("UTF-8")
      count += 1
      return false if count > max  #max回までリトライする
      puts "リトライ： #{count}"
      sleep(1)
      retry
    end
  end
end
  
class String 
  def imgsuffix
    [".jpg", ".gif", ".png", ".jpeg", ".bmp", ".JPG", ".GIF", ".PNG", ".JPEG", ".BMP"].each do |sf|
      return sf if include?(sf)
    end
    ""
  end
  
  #文字列をあらゆる n 通リに分割する
  def separate(n)
    return [[self]] if n <= 1 or n > self.length
    if n == 2
      st = self
      return [[st]] if st.length == 1
      ar = []
      (st.length - 1).times {|i| ar << [st[0..i], st[i + 1..-1]]}
      ar
    else
      seprt([[self]], n)
    end
  end
  
  def seprt(ar, n)
    if n == 2
      a = []
      ar.each do |ar1|
        b = ar1.dup
        ar1.each_with_index do |st, j|
          next if st.length == 1
          st.separate(2).each do |ar2|
            c = b.dup
            c[j] = ar2
            c.flatten!
            a << c
          end
        end
      end
      a.uniq
    else
      (n - 1).times {ar = seprt(ar, 2)}
      ar
    end
  end
  private :seprt
  
  #循環小数を分数に直す
  alias :__to_r__ :to_r
  def to_r
    s = self
    sign = 1
    if s[0] == "-"
      sign = - 1
      s = s[1..-1]
    end
    m = /(\d+)\.(\d*)\((\d+)\)$/.match(s)
    unless m
      __to_r__
    else
      a = (m[1] + "." + m[2]).__to_r__
      b = ((m[1] + m[2] + m[3]).to_i * 10 ** (- m[2].length)).to_r
      (sign * (b - a) / (10 ** m[3].length - 1)).to_r
    end
  end
  protected :__to_r__
end

class Array
  #任意の階層だけ繰り返しをネストする
  def nest_loop(&bk)
    nsloop(self, [], &bk)
  end
  
  def nsloop(ar1, ar2, &bk)
    tmp1 = ar1.dup
    time = tmp1.shift
    unless time
      bk.call(ar2)
    else
      time.times do |i|
        tmp2 = ar2.dup
        tmp2.push(i)
        nsloop(tmp1, tmp2, &bk)
      end
    end
  end
  private :nsloop
end

module Kernel
  #indexつき無限ループ
  def loop_with_index(i = 0)
    begin
      yield(i)
    end while (i += 1)
  end
end

class Rational
  #分数を循環小数に直す
  def to_rec_decimal
    st = main(self.abs)
    self.no_minus? ? st : "-" + st
  end
  
  def rec_decimal?
    slf = self.abs
    @nume = slf.numerator
    @deno = slf.denominator
    return false if @deno == 1
    get_rcycle.size == 1 ? false : true
  end

  def abs
    self.no_minus? ? self : self * (-1)
  end
  
  def no_minus?
    self.numerator >= 0
  end
  
  def no_plus?
    self.numerator <= 0
  end
  
  def main(slf)
    @nume = slf.numerator
    @deno = slf.denominator
    return "#{@nume}" if @deno == 1
    n = @nume / @deno
    ar = get_rcycle
    repetition_num = {}
    s = {}
    return "#{n}.#{ar[0][1..-1].join}" if ar.size == 1
    idx = repetition_num[@deno] = ar[1].size - ar[2]
    output_st(ar, idx, n)
  end
  
  def get_rcycle
    quotient = []
    remainder = []
    divided = @nume - (@nume / @deno) * @deno
    loop do
      quotient << divided / @deno
      a = divided % @deno
      return [quotient] if a.zero?
      if (b = remainder.index(a))
        return [quotient, remainder, b]
      end
      remainder << a
      divided = a * 10
    end
  end

  def output_st(ar, idx, n)
    st = ar[0].join[1..-1]
    if (ln = st.length) > idx
      idx = ln - idx
      "#{n}.#{st[0..(idx - 1)]}(#{st[idx..-1]})"
    else
      "#{n}.(#{st})"
    end
  end
  private :main, :get_rcycle, :output_st
end

#整数を2数の積に分ける/約数を求める
class Integer
  def divide2(include1=false)
    ar = []
    s = include1 ? 1 : 2 
    for i in s..(self ** 0.5)
      ar.push([i, self / i]) if (self % i).zero?
    end
    ar
  end
  
  def divisors
    divide2(true).flatten.uniq.sort
  end
end

class Float
  def integer?
    (self - self.to_i).zero?
  end
end

#多重配列を簡単に生成する
class Array
  def self.make(ar, ob=nil)
    raise "Argument class Error" unless ar.class == Array
    a = ar.dup
    ar1 = []
    a.shift.times {ar1 << (a.empty? ? (ob.dup rescue ob) : Array.make(a, ob))}
    ar1
  end
end

#一文字入力
module Utils
  def self.key_wait
    c = nil
    loop {break if (c = STDIN.getch)}
    STDIN.cooked!
    c
  end
end

#配列のディープコピー
class Object
  def deep_copy
    Marshal.load(Marshal.dump(self))
  end
end

#マイクロ秒まで採った現在時刻を、アルファベットの辞書順になるように変換して出力する
module Utils
  def self.time_lexic
    t = Time.now
    i = (t.to_i.to_s + sprintf("%06d", t.usec)).to_i
    ar = ("a".."z").to_a
    st = ""
    begin
      st = ar[i % 26] + st
      i /= 26
    end while i > 0
    st
  end
end

#配列の要素aをすべてbで置き換える
class Array
  def change!(a, b)
    map! {|i| (i == a) ? b : i}
  end
  
  def change(a, b)
    map {|i| (i == a) ? b : i}
  end
end