迭代多個數組的最佳方法？

Question

在Ruby中迭代多個數組的最佳方法（美觀和高效的性能）是什麼？ 比方說，我們有一個數組：

a=[x,y,z] 
b=['a','b','c'] 

，我想這一點：

x a 
y b 
z c 

感謝。

Answer 1

的zip方法在陣列上的對象：

a.zip b do |items| 
    puts items[0], items[1] 
end 

Answer 2

參見What is a Ruby equivalent for Python's "zip" builtin?

Answer 3

>> a=["x","y","z"] 
=> ["x", "y", "z"] 
>> b=["a","b","c"] 
=> ["a", "b", "c"] 
>> a.zip(b) 
=> [["x", "a"], ["y", "b"], ["z", "c"]] 
>> 

Answer 4

一種替代是使用each_with_index。快速基準測試顯示，這比使用zip稍快。

a.each_with_index do |item, index| 
    puts item, b[index] 
end 

基準：

a = ["x","y","z"] 
b = ["a","b","c"] 

Benchmark.bm do |bm| 
    bm.report("ewi") do 
    10_000_000.times do 
     a.each_with_index do |item, index| 
     item_a = item 
     item_b = b[index] 
     end 
    end 
    end 
    bm.report("zip") do 
    10_000_000.times do 
     a.zip(b) do |items| 
     item_a = items[0] 
     item_b = items[1] 
     end 
    end 
    end 
end 

結果：

 user  system  total  real 
ewi 7.890000 0.000000 7.890000 ( 7.887574) 
zip 10.920000 0.010000 10.930000 (10.918568) 

Answer 5

我喜歡通過使用Ruby多個陣列迭代時使用轉置。希望這可以幫助。的

bigarray = [] 
bigarray << array_1 
bigarray << array_2 
bigarray << array_3 
variableName = bigarray.transpose 

variableName.each do |item1,item2,item3| 

# do stuff per item 
# eg 
puts "item1" 
puts "item2" 
puts "item3" 

end