如何有条件地合并散列并添加值？

Question

我卡住合并一些哈希来得到我需要的结果。

散列包含订单总价格的细目，项目价格，税收，&送货，订购中的所有订单。我试图动态执行此操作，因为并非所有订单都收取税费，甚至不需要税或运费。

这里就是我称之为“最坏的情况”我正在处理：

#First order - has charges for Canadian GST and HST 
{:orderhdr_id=>17654122, :order_item_seq=>1, :order_item_amt_break_seq=>1, :order_item_break_type=>0, :local_amount=>8.16, :base_amount=>8.16, :orig_base_amount=>149, :tax_delivery=>0, :tax_active=>0} 
{:orderhdr_id=>17654122, :order_item_seq=>1, :order_item_amt_break_seq=>2, :order_item_break_type=>1, :local_amount=>0.41, :base_amount=>0.41, :state=>"ON", :tax_type=>"GST", :tax_rate_category=>"STD", :orig_base_amount=>7.45, :tax_rate=>5, :tax_delivery=>0, :tax_active=>1, :tx_incl=>1} 
{:orderhdr_id=>17654122, :order_item_seq=>1, :order_item_amt_break_seq=>3, :order_item_break_type=>1, :local_amount=>0.65, :base_amount=>0.65, :state=>"ON", :tax_type=>"HST", :tax_rate_category=>"STD", :orig_base_amount=>11.92, :tax_rate=>8, :tax_delivery=>0, :tax_active=>1, :tx_incl=>1} 
#Second order - has only one charge for tax 
{:orderhdr_id=>1815296, :order_item_seq=>1, :order_item_amt_break_seq=>1, :order_item_break_type=>0, :local_amount=>76.52, :base_amount=>76.52, :orig_base_amount=>99.95, :tax_delivery=>0, :tax_active=>0} 
{:orderhdr_id=>1815296, :order_item_seq=>1, :order_item_amt_break_seq=>2, :order_item_break_type=>1, :local_amount=>4.59, :base_amount=>4.59, :orig_base_amount=>6, :tax_delivery=>0, :tax_active=>1} 
#Third order - has charge for shipping 
{:orderhdr_id=>6112412, :order_item_seq=>1, :order_item_amt_break_seq=>1, :order_item_break_type=>0, :local_amount=>21.34, :base_amount=>21.34, :orig_base_amount=>99.95, :tax_delivery=>0, :tax_active=>0} 
{:orderhdr_id=>6112412, :order_item_seq=>1, :order_item_amt_break_seq=>2, :order_item_break_type=>2, :local_amount=>4.7, :base_amount=>4.7, :orig_base_amount=>22, :tax_delivery=>0, :tax_active=>0} 

的:order_item_break_type决定了它是什么类型的收费，项目，税收，航运。

如果:order_item_break_type为0或2，然后从:orig_base_amount减去:base_amount并将其添加到该中断类型的整体总。对于:order_item_break_type等于1，我需要总结:orig_base_amount和:base_amount,的差异，但是我需要将不同的税分开。

因此，这里是我应该与上面的命令结束了一下：

:break_type = 0 | total = 242.88 
:break_type = 1, :state = ON, :tax_type = GST, :tax_rate_category = STD | total = 7.04 
:break_type = 1, :state = ON, :tax_type = HST, :tax_rate_category = STD | total = 11.27 
:break_type = 1 | total = 1.41 
:break_type = 2 | total = 17.30 

我有叫@amounts数组这些哈希值。

我有像merge!,inject,shift和更多的方法，通过我的头，但不能把它放在一起。

Answer 1

这个怎么样？不过，我真的不知道你在那里做什么。

@amounts = [ 
#First order - has charges for Canadian GST and HST 
{:orderhdr_id=>17654122, :order_item_seq=>1, :order_item_amt_break_seq=>1, :order_item_break_type=>0, :local_amount=>8.16, :base_amount=>8.16, :orig_base_amount=>149, :tax_delivery=>0, :tax_active=>0}, 
{:orderhdr_id=>17654122, :order_item_seq=>1, :order_item_amt_break_seq=>2, :order_item_break_type=>1, :local_amount=>0.41, :base_amount=>0.41, :state=>"ON", :tax_type=>"GST", :tax_rate_category=>"STD", :orig_base_amount=>7.45, :tax_rate=>5, :tax_delivery=>0, :tax_active=>1, :tx_incl=>1}, 
{:orderhdr_id=>17654122, :order_item_seq=>1, :order_item_amt_break_seq=>3, :order_item_break_type=>1, :local_amount=>0.65, :base_amount=>0.65, :state=>"ON", :tax_type=>"HST", :tax_rate_category=>"STD", :orig_base_amount=>11.92, :tax_rate=>8, :tax_delivery=>0, :tax_active=>1, :tx_incl=>1}, 
#Second order - has only one charge for tax 
{:orderhdr_id=>1815296, :order_item_seq=>1, :order_item_amt_break_seq=>1, :order_item_break_type=>0, :local_amount=>76.52, :base_amount=>76.52, :orig_base_amount=>99.95, :tax_delivery=>0, :tax_active=>0}, 
{:orderhdr_id=>1815296, :order_item_seq=>1, :order_item_amt_break_seq=>2, :order_item_break_type=>1, :local_amount=>4.59, :base_amount=>4.59, :orig_base_amount=>6, :tax_delivery=>0, :tax_active=>1}, 
#Third order - has charge for shipping 
{:orderhdr_id=>6112412, :order_item_seq=>1, :order_item_amt_break_seq=>1, :order_item_break_type=>0, :local_amount=>21.34, :base_amount=>21.34, :orig_base_amount=>99.95, :tax_delivery=>0, :tax_active=>0}, 
{:orderhdr_id=>6112412, :order_item_seq=>1, :order_item_amt_break_seq=>2, :order_item_break_type=>2, :local_amount=>4.7, :base_amount=>4.7, :orig_base_amount=>22, :tax_delivery=>0, :tax_active=>0}, 
] 

@totals = Hash.new(0) 

@amounts.group_by{|row| row[:order_item_break_type]}.each do |break_type, rows| 

    rows.each do |row| 

    key = [break_type, row[:tax_type]] 
    @totals[key] += row[:orig_base_amount] - row[:base_amount] 

    end 
end 

@totals 
# => {[0, nil]=>242.88, 
#  [1, "GST"]=>7.04, 
#  [1, "HST"]=>11.27, 
#  [1, nil]=>1.4100000000000001, 
#  [2, nil]=>17.3}