Changing hash key

Ruby
1

I am working with a script to record accounts and their balances. I
need to check the key in a hash and if the account number is already
there just add the blanace to the value. So far this is what I have and
its not quite doing what I need. Is my test not right? I get all the
account numbers and their balances instead of a list with the accounts
and balances without the duplicate account numbers.

Thanks,
Tim

sktylist = Hash.new("")
if sktylist.has_key?(’@acctnum’)
sktylist.merge!(’@acctnum’ => ‘value’)
else
sktylist[@acctnum] = [value]
end
sktylist.each { |key, value| puts “#{key} equals #{value}”
}

2

This is not working because you’re using a string called ‘@acctnum’
instead of the content of the variable @acctnum inside both has_key? and
merge functions

First remove ’ signs from that functions, next I suggest you to use
symbols instead
of variables for keys (@acctnum.to_sym instead of @acctnum)

Bye

sktylist = Hash.new("")
if sktylist.has_key?(’@acctnum’)
sktylist.merge!(’@acctnum’ => ‘value’)
else
sktylist[@acctnum] = [value]
end
sktylist.each { |key, value| puts “#{key} equals #{value}”
}

3

Sandro P. wrote:

This is not working because you’re using a string called ‘@acctnum’
instead of the content of the variable @acctnum inside both has_key? and
merge functions

First remove ’ signs from that functions, next I suggest you to use
symbols instead
of variables for keys (@acctnum.to_sym instead of @acctnum)

Bye

sktylist = Hash.new("")
if sktylist.has_key?(’@acctnum’)
sktylist.merge!(’@acctnum’ => ‘value’)
else
sktylist[@acctnum] = [value]
end
sktylist.each { |key, value| puts “#{key} equals #{value}”
}

I’ve created the hash and can store all keys and values however I’m
trying += to add the balances which is value in the hash. So far the
accounts that have the same number are not being consolidated into one
key, value… Can someone tell me what I’m doing wrong with this?

Thanks,
Tim

sktylist = Hash.new("")
sktylist[@acctnum] += [value]
p sktylist

4

On Wed, May 7, 2008 at 7:00 PM, Tim W. [email protected] wrote:

trying += to add the balances which is value in the hash. So far the

Given the limited amount of information I have I would guess that you
might doing this

TypeError: can’t convert Array into String

wrong.

HTH
Robert

–
http://ruby-smalltalk.blogspot.com/

Whereof one cannot speak, thereof one must be silent.
Ludwig Wittgenstein

5

How about:

sktylist = Hash.new
sktylist.[@acctnum] ||= 0
sktylist.[@acctnum] += value

by
TheR

6

Damjan R. wrote:

  sktylist = Hash.new
  sktylist.[@acctnum] ||= 0

sktylist = Hash.new(0)