Question

我的代码在这里

str= "In 2004, Obama received national attention during his campaign to represent Illinois in the United States Senate"
 arr =str.scan(/\S+(?:\s+\S+)?/)
 it gives
 arr=["In 2004,", "Obama received", "national attention", "during his", "campaign to", "represent Illinois", "in the", "United States", "Senate"]
   fresh_arr=[]
   arr.each do |el|
     if !arr.match(/is|am|are|this|his/)
        fresh_arr << el
     end
   end

现在我要删除包含（is，am，are，this，his）类型字符串的元素然后结果像这样

arr=["Obama received", "national attention","represent Illinois","United States", "Senate"]

我有非常大的数据，我可以花6秒时间以任何其他方式执行此操作

Answer 1

简单的方法。但我不知道表现。因为map仍然运行您正在运行的循环。

   arr.map{|x| x unless x =~ /\b(in|am|are|his|this)\b/i}.compact

基准：

> my_bm(500000){arr.map{|x| x unless x =~ /\b(in|am|are|his|this)\b/i}.compact}
      user     system      total        real
  7.430000   0.000000   7.430000 (  7.451064)
 => nil 

> my_bm(500000){arr.reject! { |e| e =~ /\b(in|am|are|his|this)\b/i }}
      user     system      total        real
  4.620000   0.000000   4.620000 (  4.623782)


> my_bm(5000000){arr.map{|x| x unless x =~ /\b(in|am|are|his|this)\b/i}.compact}
      user     system      total        real
 50.790000   0.010000  50.800000 ( 50.840533)

> my_bm(5000000){arr.reject! { |e| e =~ /\b(in|am|are|his|this)\b/i }}
      user     system      total        real
 46.140000   0.010000  46.150000 ( 46.198752)
 => nil

从字符串中删除元素

1 个答案: