From: Todd Benson <caduceass@...>
Date: 2008-05-15T03:00:47+09:00
Subject: Re: changing hash key

On Wed, May 14, 2008 at 11:53 AM, Tim Wolak <tim.wolak@gmail.com> wrote:
> Hmm ok then maybe changing the keys is not what I need to do then.
>
> The reason I have skty and sktyny is that those are account names, sorry
> should have stated that earlier.  So I have a list of account numbers
> and their balances, all accounts listed 500 through 539 should have a
> key of skty and accounts with 540 through 550 should be sktyny.  All the
> account balances for skty should be combined into the value for skty
> and all the balances should be combined for teh value of sktyny.  Here
> is the full code, I did not want to post  a mile long request with it
> all in there.
>
> Tim
>
>
>
> class SktyFut
>  attr_reader :acct
>
>  def initialize(filename)
>   @acct = File.new(filename, "r")

I'm not sure ruby automagically closes the file when the instance of
SktyFut is garbage collected.  You open a file and assign it to a
class instance variable.  Looks a little scary to me.

>  end
>
>    def future_data
>      @sktylist = Hash.new(0)
>      @acct.each do |list|
>        office = list[21..23]
>          if office == "RPT"
>            next
>          else
>            acctnum = list[24..28]
>          end
>          lv = list[217..230]
>          is_negative = list[215,1] == "-"
>          value = lv.to_f/100
>          value = -value if is_negative

value = list[215..230].delete(' ').to_f/100
# if the character separating - from lv is a space

>
>          # Add vales to hash
>
>          @sktylist[acctnum] += value
>        end
>          return @sktylist
>    end
> end
>
>          class Calculate
>            attr_reader :sktyfuta, :sktyfutb
>              def initialize(sktyfuta, sktyfutb)
>                @sktyfuta = sktyfuta
>                @sktyfutb = sktyfutb
>              end
>
>                  def data_comp
>                    @sktyfuta.merge(@sktyfutb) { |key, old_value,
> new_value| old_value - new_value }
>                  end
>                #end
>          end
>
>          class FinalNum
>            attr_reader :sktynl
>              def initialize(sktynl)
>                @sktynl = sktynl
>              end
>
>                def numbers
>                  @skty = Hash.new(0)
>                  @sktynl.each do |key, value|
>                    if key <= "539"

>                      key.to_s
>                      key = "SKTY"
>                      @skty[key] += value

replace above 3 lines with... @skty["SKTY"] += value

>                    elsif key >="540"
>                      key = "SKYNY"
>                      @skty[key] += value

replace above 3 lines with... @skty["SKYNY"] += value
or SKTYNY or whatever it is you are using

>                    end
>                      #@skty.each{ |key, value| puts "#{key} value
> #{value}" }
>

   Here should be... return @skty

>                  end
>                end
>              end
>
> Dir.chdir("/tmp")
> post = SktyFut.new("SKTYFutBal20080513.txt")
> a = post.future_data
> #a.each{|key, value| puts "#{key} value is #{value}"}
> pre = SktyFut.new("SKTYFutBal20080512.txt")
> b = pre.future_data
> data = Calculate.new(a,b)
> iteration = data.data_comp
> iteration.sort
> #iteration.each{|key, value| puts "#{key} comp equals #{value}" }
> sktyfinal = FinalNum.new(iteration)
> submission = sktyfinal.numbers
> submission.each{ |key, value| puts "#{key} line is #{value}" }

For the #numbers method, you might someday want to check out #select.
For example.

skny_sum = @sktynl.select {|k, v| k < 540}.inject(0) {|sum, arr| sum + arr[1]}

hth,
Todd