Hash

Hi

iv started writing a class which reads the data from a text file and
counts the number of Tags

however im having a struggle as I want to split the tag and the data
into a hash i.e the Tag is the index and the data is the rest

if anyone could provide me with any psuedo code i'd be very appreciative
my code is below

Many Thanks

text file:

Tag: ref1
Type: Book
Author: Little, S R

Tag: ref2
Type: Journal
Author: Smith, J

Tag: ref3
Type: Conference Paper
Author: Williams, M

Tag: ref4
Type: Book
Author: Jones, M B

ruby class:

#!/usr/local/bin/ruby

···

#
#
#
  require 'getoptlong'

  opts = GetoptLong.new(
    ['--style', '-n', GetoptLong::NO_ARGUMENT ],
    ['--database', '-i', GetoptLong::REQUIRED_ARGUMENT]
  )

  $linecount = 0

  opts.each do |opt, arg|
    case opt
      when '--style'
         require arg
      when '--database'
    end
  end
#
#
#
# process options
#
#
#
  File.open('reference.txt').each do |line|
    if line =~ /^tag:/i
      $linecount += 1
    end
  end
    puts $linecount
#
--
Posted via http://www.ruby-forum.com/.

Johnathan Smith wrote:

  File.open('reference.txt').each do |line|
    if line =~ /^tag:/i
      $linecount += 1
    end
  end
    puts $linecount
#

try something like this:

linecount = 0
results =
hash = {}
File.open('reference.txt').each do |line|
  m = line.match /^(\w+):\s*([\w+,\s]+)$/
  unless m
    results << hash unless hash.empty?
    hash = {}
  else
    linecount += 1
    hash[m[1]] = m[2].chomp
  end
end

···

--
Posted via http://www.ruby-forum.com/\.

info = {}
last_tag = nil

# Could be File.readlines
DATA.each_line{ |line|
  _, key, data = line.match( /^(\w+): (.+)/ ).to_a
  next unless key # skip blank lines
  if key == "Tag"
    last_tag = data
    info[ data ] = {}
  else
    info[ last_tag ][ key ] = data
  end
}

require 'pp'
pp info
#=> {"ref4 "=>{"Author"=>"Jones, M B", "Type"=>"Book "},
#=> "ref3 "=>{"Author"=>"Williams, M ", "Type"=>"Conference Paper "},
#=> "ref2 "=>{"Author"=>"Smith, J ", "Type"=>"Journal "},
#=> "ref1 "=>{"Author"=>"Little, S R ", "Type"=>"Book "}}

__END__
Tag: ref1
Type: Book
Author: Little, S R

Tag: ref2
Type: Journal
Author: Smith, J

Tag: ref3
Type: Conference Paper
Author: Williams, M

Tag: ref4
Type: Book
Author: Jones, M B

···

On Dec 4, 7:30 am, Johnathan Smith <stu...@hotmail.com> wrote:

iv started writing a class which reads the data from a text file and
counts the number of Tags

however im having a struggle as I want to split the tag and the data
into a hash i.e the Tag is the index and the data is the rest

if anyone could provide me with any psuedo code i'd be very appreciative
my code is below

Many Thanks

text file:

Tag: ref1
Type: Book
Author: Little, S R

Tag: ref2
Type: Journal
Author: Smith, J

Tag: ref3
Type: Conference Paper
Author: Williams, M

Tag: ref4
Type: Book
Author: Jones, M B

Here's another variation:

# Could be IO.read
info = Hash[ *DATA.read.split( /\n\n+/ ).map{ |chunk|
  pieces = chunk.scan /^(\w+): (.+)/
  first = pieces.shift
  raise "Uhm...I was assuming Tag comes first" unless first[0] ==
"Tag"
  [ first[1], Hash[ *pieces.flatten ] ]
}.flatten ]

require 'pp'
pp info
#=> {"ref4 "=>{"Author"=>"Jones, M B", "Type"=>"Book "},
#=> "ref3 "=>{"Author"=>"Williams, M ", "Type"=>"Conference Paper "},
#=> "ref2 "=>{"Author"=>"Smith, J ", "Type"=>"Journal "},
#=> "ref1 "=>{"Author"=>"Little, S R ", "Type"=>"Book "}}

__END__
Tag: ref1
Type: Book
Author: Little, S R

Tag: ref2
Type: Journal
Author: Smith, J

Tag: ref3
Type: Conference Paper
Author: Williams, M

Tag: ref4
Type: Book
Author: Jones, M B

···

On Dec 4, 8:19 am, Phrogz <phr...@mac.com> wrote:

On Dec 4, 7:30 am, Johnathan Smith <stu...@hotmail.com> wrote:
> iv started writing a class which reads the data from a text file and
> counts the number of Tags

> however im having a struggle as I want to split the tag and the data
> into a hash i.e the Tag is the index and the data is the rest

Hi,

thanks for the awesome response I appreciate it

however, i think i may have misunderstood what i was trying to achieve.

what i want to do is to create an empty hash every time it encounters a
Tag
line, and if it encounters any other field, put the field and the
related
value in the hash, using the field name (e.g Type and Author) as the key

im not sure if any of the help you provived achieves this but any help
on this matter would be greatly appreciated

many thanks

···

--
Posted via http://www.ruby-forum.com/.

Unless I'm misunderstanding you, both of the solutions I provided do
what you are describing.

You can even see this logic explicitly here, in the first solution:
   if key == "Tag"
    last_tag = data
    info[ data ] = {}
  else
    info[ last_tag ][ key ] = data
  end

Does the output not look like what you expect?

  pp info
  #=> {"ref4 "=>{"Author"=>"Jones, M B", "Type"=>"Book "},
  #=> "ref3 "=>{"Author"=>"Williams, M ", "Type"=>"Conference Paper
"},
  #=> "ref2 "=>{"Author"=>"Smith, J ", "Type"=>"Journal "},
  #=> "ref1 "=>{"Author"=>"Little, S R ", "Type"=>"Book "}}

If not, what actual output did you want?

···

On Dec 4, 9:42 am, Johnathan Smith <stu...@hotmail.com> wrote:

what i want to do is to create an empty hash every time it encounters a
Tag
line, and if it encounters any other field, put the field and the
related
value in the hash, using the field name (e.g Type and Author) as the key

im not sure if any of the help you provived achieves this but any help
on this matter would be greatly appreciated

im just expecting an output of every time it encounters a tag to create
an empty hash containing the other fields using the fields as the key

im having trouble getting the code u provided to work can you see my
errors?

···

#
#
  require 'getoptlong'

  opts = GetoptLong.new(
    ['--style', '-n', GetoptLong::NO_ARGUMENT ],
    ['--database', '-i', GetoptLong::REQUIRED_ARGUMENT]
  )

  $linecount = 0

  opts.each do |opt, arg|
    case opt
      when '--style'
         require arg
      when '--database'
    end
  end
#
#
#
# process options
#
#
#
  File.open('reference.txt').each do |line|
    if line =~ /^tag:/i
      $linecount += 1
    end
  end
    puts $linecount

  info = {}
  last_tag = nil

  data.each_line{ |line| _, key, data = line.match( /^(\w+): (.+)/
).to_a
  next unless key # skip blank lines
  if key == "Tag"
    last_tag = data
    info[ data ] = {}
  else
    info[ last_tag ][ key ] = data
  end
  }
#
#
--
Posted via http://www.ruby-forum.com/.