Question

我想将这个ruby哈希结构转换为哈希数组。结束结构将在图表api中使用，提前谢谢

发件人：

data = 
    {
        ["Transportations", "Not-Approved"] => 350,
        ["Transportations", "Approved"]     => 160,
        ["Communications",  "Not-Approved"] => 300,
        ["Communications","Approved"]       => 80,
        ["Rentals","Not-Approved"]          => 50,
        ["Rentals", "Approved"]             => 145,
        ["Salaries","Not-Approved"]         => 150,
        ["Salaries", "Approved"]            => 310
    }

要

data = [
    {
        name: "Transportations",
        data: [["Not-Approved", 350], ["Approved", 160]]
    },
    {
        name: "Communications",
        data: [["Not-Approved", 300], ["Approved", 80]]
    },
    {
        name: "Rentals",
        data: [["Not-Approved", 50], ["Approved", 145]]
    },
    {
        name: "Salaries",
        data: [["Not-Approved", 150], ["Approved", 310]]
    }
]

Answer 1

<强>代码

def rearrange(data)
  data.group_by { |k,_| k.first }.map { |name, arr|
    { name: name, data: arr.map { |(_,outcome), val| [outcome, val] } } }
end

示例

data = { ["Transportations", "Not-Approved"] => 350, ["Transportations", "Approved"] => 160, ["Communications", "Not-Approved"] => 300, ["Communications","Approved"] => 80, ["Rentals","Not-Approved"] => 50, ["Rentals", "Approved"] => 145, ["Salaries","Not-Approved"] => 150, ["Salaries", "Approved"] => 310 } rearrange(data) #=> [{:name=>"Transportations", # :data=>[["Not-Approved", 350], ["Approved", 160]]}, # {:name=>"Communications", # :data=>[["Not-Approved", 300], ["Approved", 80]]}, # {:name=>"Rentals", # :data=>[["Not-Approved", 50], ["Approved", 145]]}, # {:name=>"Salaries", # :data=>[["Not-Approved", 150], ["Approved", 310]]} # ]

<强>解释

第一步如下。

h = data.group_by { |k,_| k.first } #=> { "Transportations"=>[ # [["Transportations", "Not-Approved"], 350], # [["Transportations", "Approved"], 160] # ], # "Communications"=>[ # [["Communications", "Not-Approved"], 300], # [["Communications", "Approved"], 80] # ], # "Rentals"=>[ # [["Rentals", "Not-Approved"], 50], # [["Rentals", "Approved"], 145] # ], # "Salaries"=>[ # [["Salaries", "Not-Approved"], 150], # [["Salaries", "Approved"], 310] # ] # }

Enumerable#group_by的第二个块变量保存键的值（键是第一个块变量）。例如，当密钥为["Transportations", "Not-Approved"]时，该值为350。我已将块变量_（一个有效的局部变量）赋给该值，主要是为了通知读者它在块计算中没有使用。

要理解第二步，h键值对的映射，首先定义

enum = h.map #=> #<Enumerator: # {"Transportations"=>[ # [["Transportations", "Not-Approved"], 350], # [["Transportations", "Approved"], 160] # ], "Communications"=>[ # ... # [["Salaries", "Approved"], 310]]}:map>

生成enum的第一个元素并将其传递给块，并使用并行赋值为块变量赋值。

name, arr = enum.next #=> ["Transportations", [ # [["Transportations", "Not-Approved"], 350], # [["Transportations", "Approved"], 160] # ] # ] name #=> "Transportations" arr #=> [ # [["Transportations", "Not-Approved"], 350], # [["Transportations", "Approved"], 160] # ]
然后执行
map的块计算。首先，计算

a = arr.map { |(_,outcome), val| [outcome, val] } #=> [["Not-Approved", 350], ["Approved", 160]]

然后构造“运输”的哈希值。

{ name: name, data: a } #=> {:name=>"Transportations", # :data=>[["Not-Approved", 350], ["Approved", 160]]}

其余的计算方法类似。

Answer 2

试试这个，

h = Hash.new { |h, k| h[k] = { name: k, data: {} }}
data.each { |(name, each), value| h[name][:data][each] = value };
h.values.each { |each| each[:data] = each[:data].to_a }
array = h.values

将哈希值更改为哈希数组

2 个答案: