我要特别按其他阵列排列一个阵列。
EX:审议阵列
a=["one", "two", "three"]
b=["two", "one", "three"]
Now I want to sort array a in the order of b , i.e
a.each do |t|
# It should be in the order of b
puts t
end
因此,产出应当
two
one
three
任何建议?
我要特别按其他阵列排列一个阵列。
EX:审议阵列
a=["one", "two", "three"]
b=["two", "one", "three"]
Now I want to sort array a in the order of b , i.e
a.each do |t|
# It should be in the order of b
puts t
end
因此,产出应当
two
one
three
任何建议?
Array#sort_by is what you re after.
a.sort_by do |element|
b.index(element)
end
3. 针对评论的更可衡量的版本:
a=["one", "two", "three"]
b=["two", "one", "three"]
lookup = {}
b.each_with_index do |item, index|
lookup[item] = index
end
a.sort_by do |item|
lookup.fetch(item)
end
如果b
包括a
的所有内容,如果内容是独特的,则:
puts b & a
假设<条码>a条码>,就<条码>b条码>中各项内容的顺序排列。
sorted_a =
a.sort do |e1, e2|
b.index(e1) <=> b.index(e2)
end
I normally use this to sort error messages in ActiveRecord
in the order of appearance of fields on the form.
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