将数组拆分为子数组

Question

我有一个哈希数组，我想打破一个子数组数组。

拆分的触发器是：group

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" }

是否有快速导轨功能可以实现这一点，或者我需要使用控制中断类型循环，就像我多年前使用Cobol一样......：）

Answer 1

您可能希望使用Enumerable.group_by功能对数据进行分组。

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

这会产生

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

Answer 2

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