Ruby在哈希中组合元素

我有一个看起来像这样的：

data = {abc -> [[date1, val1], [date2,val2]], def -> [[date1,val3], [date2,val4]]} 

我想加入abc和def元素，所以就像这样：

 data = {join -> [[date1, val1+val3], [date2, val2+val4]] } 

我该如何解决这个问题。 请注意，哈希中还有其他元素不应被修改。

Answer 1

我假设abc ， def和join实际上是符号。

 a = Hash[data.delete(:abc)] # extract data[:abc] and convert it to a Hash ("a") b = Hash[data.delete(:def)] # extract data[:def] and convert it to a Hash ("b") data[:join] = a.map do |k,v| # iterate over one of the extracted Hashes [k, v + (b[k] || 0)] # for each key, return a 2-item array with the key, end # and the sum of the values from "a" and "b"