將數組拆分爲子數組

Question

我有一個散列數組，我想打入子數組數組。

爲分體式的觸發是：組

master = [] 
master << { id: 1, group: "Brown", name: "Fred" } 
master << { id: 2, group: "Brown", name: "May" } 
master << { id: 3, group: "Brown", name: "Brian" } 
master << { id: 4, group: "Black", name: "Sue" } 
master << { id: 5, group: "Orange", name: "Helen" } 
master << { id: 6, group: "Orange", name: "Peter" } 
master << { id: 7, group: "Red", name: "Grace" } 
master << { id: 8, group: "Red", name: "Michael" } 
master << { id: 9, group: "Red", name: "Paul" } 

是否有一個快速的軌道功能，可以實現這一點還是我需要爲我使用COBOL年前一樣使用控制斷型環.. :)

Answer 1

你會使用Enumerable.group_by函數希望將你的數據。

master.group_by { |item| item[:group] } 

這將產生

{ 
    "Red" => [{ id: 7, group: "Red", name: "Grace" },...], 
    "Black" => ..., 
    ... 
} 

Answer 2

master.group_by{|h| h[:group]}