Question

我有一个arr3 = ["Ac,Ab,Aa", "Ba,Bb,Bd", "Ca,Cc,Cb", "Dd,Da,Dc", "aA,aC,aD", "bD,bA,bB", "cB,cA,cC", "dD,dC,dA"]和item = ["dD"]的数组。我想要消除那些有＆＃34; dD＆＃34;或者＆＃34; Dd＆＃34;。

我想要的结果是[＆＃34; Ac，Ab，Aa＆＃34;，＆＃34; Ba，Bb，Bd＆＃34;，＆＃34; Ca，Cc，Cb＆＃34;，＆＃34 ; aA，aC，aD＆＃34;，＆＃34; bD，bA，bB＆＃34;，＆＃34; cB，cA，cC＆＃34;]。

我尝试了以下操作，但它没有用，它没有过滤掉任何项目，因此arr3保持不变：

arr3 = ["Ac,Ab,Aa", "Ba,Bb,Bd", "Ca,Cc,Cb", "Dd,Da,Dc",
        "aA,aC,aD", "bD,bA,bB", "cB,cA,cC", "dD,dC,dA"] 
item = ["dD"]

def eliminate (from, item) 
  item1 =  item.join
  item2 = item1.reverse
  from.select { |pair| !pair.include? item1 or !pair.include? item2} 
end

eliminate(arr3, item)

Answer 1

这样的东西？

def eliminate from, item
  from.reject { |e| e.include? item.join } &
  from.reject { |e| e.include? item.join.reverse }
end

eliminate arr3, item
# ["Ac,Ab,Aa", "Ba,Bb,Bd", "Ca,Cc,Cb", "aA,aC,aD", "bD,bA,bB", "cB,cA,cC"]

或者这个！

def eliminate from, item
  from.reject do |e|
    e.include?(item.join) || e.include?(item.join.reverse)
  end
end

eliminate arr3, item
# ["Ac,Ab,Aa", "Ba,Bb,Bd", "Ca,Cc,Cb", "aA,aC,aD", "bD,bA,bB", "cB,cA,cC"]

Answer 2

将条件更改为and

from.select { |pair| !pair.include? item1 and !pair.include? item2}

Answer 3

由于您的情况，您的代码无法正常工作：

!pair.include? item1 or !pair.include? item2

你有条件＆＃34;倒退＆＃34;因为您使用or代替and。你想要其中一个：

!pair.include?(item1) && !pair.include?(item2)
# or
!(pair.include?(item1) || pair.include?(item2))

这是因为De Morgan's boolean conversion laws。我们假设您有两个条件A和B。然后

not(A or B) = not(A) and not(b)
not(A and B) = not(A) or not(B)

您希望pair不包含item1 和 item2，这就是原因：

!pair.include?(item1) && !pair.include?(item2)

是一种自然而正确的表达方式。

Answer 4

不雅但有效（＆＃34; brutto ma buono＆＃34;）：

arr3 = ["Ac,Ab,Aa", "Ba,Bb,Bd", "Ca,Cc,Cb", "Dd,Da,Dc", "aA,aC,aD", "bD,bA,bB", "cB,cA,cC", "dD,dC,dA"]
item = ["dD"]
result = arr3.delete_if do |element|
  triad = element.split(",")
  triad.member?(item[0]) or triad.member?(item[0].reverse)
end
p result

Answer 5

arr3.reject { |str| str =~ /#{item.first}|#{item.first.reverse}/ }
  #=> ["Ac,Ab,Aa", "Ba,Bb,Bd", "Ca,Cc,Cb", "aA,aC,aD", "bD,bA,bB", "cB,cA,cC"]

如何消除具有一定价值的数组项

5 个答案: