ruby on rails - Group model objects by and calculate min/max/count -


i trying group name , brand , minimum value of price, maximum value of price, average value of price , count value. activemodel, not active record.

model:

class product   include activemodel::model   attr_accessor :name, :brand, :price, :value end

expected output:

name:"big", brand:"sony", price_min:10, price_max:10, price_avg:10, count_value:2 name:"small", brand:"car", price_min:10, price_max:13, price_avg:11.5, count_value:2 name:"round", brand:"car", price_min:14, price_max:14, price_avg:14, count_value:1 name:"horse", brand:"car", price_min:10, price_max:10, price_avg:10, count_value:1

please help.

code:

myarray = []  myarray << product.new({name: "big", brand: "sony", price: 10, value: 5}) myarray << product.new({name: "big", brand: "sony", price: 10, value: 2}) myarray << product.new({name: "small", brand: "car", price: 13, value: 3}) myarray << product.new({name: "small", brand: "car", price: 10, value: 4}) myarray << product.new({name: "round", brand: "car", price: 14, value: 5}) myarray << product.new({name: "horse", brand: "car", price: 10, value: 6})  myarray 

grouped_products = myarray.group_by |product|   [product.name , product.brand] end  grouped_products.map |_, v|   [      [ :name, v[0].name ],     [ :brand, v[0]. brand ],      [ :price_min, v.min_by { |p| p.price }.price ],     [ :price_max, v.max_by { |p| p.price }.price ],     [ :price_avg, v.sum { |p| p.price } / v.count ],     [ :count_value, v.count ]   ].to_h end

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