Question

我正在尝试对某些记录进行分组，但很可能是效率低下。需要帮助 -

首先，我从处理过的一堆文件中收集了以下一组数据 -
BookA - section1，section2
BookB - 第2节，第4节

我使用了hh = Hash.new {| h，k | h [k] = {}}并将其存储为 -

hh[BookA][section1] = BookA
hh[BookA][section2] = BookA
hh[BookB][section2] = BookB
hh[BookB][section4] = BookB

但是我需要打印所有这些如下 -
第1节 - BookA
第2节 - BookA
第2节 - BookB
第4节 - BookB

有关如何做到这一点的任何建议......

所以我创造了 h = Hash.new {| h，k | H [K] = []}
section_hash = Hash.new（[]）
迭代 -
h.each do | k，v |
v.each do | s |
put＆＃34;＃{s} - ＃{k}＆＃34;
fh [s]＆lt;＆lt; ķ
结束
结束
放fh
它正确打印所有内容但是fh是零，任何想法都是错误的.... 输出来自puts命令
s1 - b1
s2 - b1
s2 - b2

Answer 1

我可以通过将此部分用作哈希键来实现，如下所示：

# so this will create a new empty array for any keys we add
section_hash = Hash.new([])

# you can grab out the lines of the file or use each to do it line by line.
book_lines = File.readlines("my_file.txt")

# now go through each of these and add the data into the hash
book_lines.each do |line|

  # convert each line to a key/value pair
  # eg "BookA - section1, section2"
  # {"BookA" => ["section1", "secton2"]}
  book, sections = line.split(" - ")
  sections = sections.split(', ')    

  # and hash away these values
  sections.each do |section|
     section_hash[section] << book
  end
end

然后你可以打印：

section_hash.each do |section, books|
  # you may choose to uniq (in case of double ups)
  books.uniq.each do |book|
    puts "#{section} - #{book}"
  end
end

散列值为Hash或Array Ruby

1 个答案: