如何计算Ruby 1.8.5中的重复哈希值（Sketchup Ruby API）
我需要计算重复项，它们需要100％相同以增加我的计数，但我不能使用Ruby 1.8.5中的任何内容，此代码将在google sketchup中的插件中运行
Google Sketchup Ruby API
puts VERSION 1.8.5 puts RUBY_PLATFORM i686-darwin8.10.1 product = 'Glass' x = width y = length z = density product_list = [ { "product" => 1, "x" => 200, "y" => 100, "z" => 18}, { "product" => 1, "x" => 200, "y" => 100, "z" => 18}, { "product" => 1, "x" => 300, "y" => 100, "z" => 18}, { "product" => 2, "x" => 300, "y" => 100, "z" => 18}, { "product" => 2, "x" => 100, "y" => 100, "z" => 18}, { "product" => 2, "x" => 100, "y" => 100, "z" => 18}, { "product" => 3, "x" => 100, "y" => 100, "z" => 18} ]; product_list_result = product_list.count_duplicate(); product_list_result = [ { "product" => 1, "x" => 200, "y" => 100, "z" => 18, "count" = 2}, { "product" => 1, "x" => 300, "y" => 100, "z" => 18, "count" = 1}, { "product" => 2, "x" => 300, "y" => 100, "z" => 18, "count" = 1}, { "product" => 2, "x" => 100, "y" => 100, "z" => 18, "count" = 2}, { "product" => 3, "x" => 100, "y" => 100, "z" => 18, "count" = 1} ]; 简短回答：
h = Hash.new 0 product_list.each {|p| h[p] += 1} product_list_result = h.keys.map{|k| k["count"] = h[k]; k}
更长的答案解释这是如何工作的。 从您的数据开始：
product_list = [ { "product" => 1, "x" => 200, "y" => 100, "z" => 18}, { "product" => 1, "x" => 200, "y" => 100, "z" => 18}, { "product" => 1, "x" => 300, "y" => 100, "z" => 18}, { "product" => 2, "x" => 300, "y" => 100, "z" => 18}, { "product" => 2, "x" => 100, "y" => 100, "z" => 18}, { "product" => 2, "x" => 100, "y" => 100, "z" => 18}, { "product" => 3, "x" => 100, "y" => 100, "z" => 18} ]; # First, create a hash to count the number of unique products. Have the initial # count be 0. h = Hash.new 0 # Add each product to the hash count. product_list.each {|p| h[p] += 1}
现在，您有一个产品作为键的哈希值，并计为值：
h = {{"z"=>18, "y"=>100, "x"=>100, "product"=>3}=>1, {"z"=>18, "y"=>100, "x"=>300, "product"=>1}=>1, {"z"=>18, "y"=>100, "x"=>200, "product"=>1}=>2, {"z"=>18, "y"=>100, "x"=>300, "product"=>2}=>1, {"z"=>18, "y"=>100, "x"=>100, "product"=>2}=>2}
现在将其转换为您想要的数组格式：
product_list_result = [] h.keys.each do |k| # since each key is a product hash, we can add count to it k["count"] = h[k] # Now, add that to the array product_list_result << k end
结果如下：
product_list_result = [ {"z"=>18, "y"=>100, "x"=>100, "product"=>3, "count"=>1}, {"z"=>18, "y"=>100, "x"=>300, "product"=>1, "count"=>1}, {"z"=>18, "y"=>100, "x"=>200, "product"=>1, "count"=>2}, {"z"=>18, "y"=>100, "x"=>300, "product"=>2, "count"=>1}, {"z"=>18, "y"=>100, "x"=>100, "product"=>2, "count"=>2} ]
arrays转换可以更简洁地完成：
product_list_result = h.keys.map{|k| k["count"] = h[k]; k}
h.keys从哈希h返回一个键数组，这只是列表中的唯一产品。 然后，函数映射将该数组中的每个对象替换为后面的块的结果，该块仅将计数值添加到产品哈希。
product_list.dup.group_by { |h| h }.each_value.map do |value| value.first.tap { |hash| hash['count'] = value.count } end => [{"product"=>1, "x"=>200, "y"=>100, "z"=>18, "count"=>2}, {"product"=>1, "x"=>300, "y"=>100, "z"=>18, "count"=>1}, {"product"=>2, "x"=>300, "y"=>100, "z"=>18, "count"=>1}, {"product"=>2, "x"=>100, "y"=>100, "z"=>18, "count"=>2}, {"product"=>3, "x"=>100, "y"=>100, "z"=>18, "count"=>1}]
dup是为了不修改原始product_list
测试ruby 1.8.7