Help with Multi Dimensional Array


#1

I’m new to ruby and have been trying to figure out what I’m doing
wrong.

I’m completely stumped about how to merge two files together based on
whether they share the same key or not.

Example:

File 1
ALPHA|OMEGA|GAMMA
1 | 2 | 3
4| 5| 6

File 2
EPSILON|GREEK|OMEGA|BETA
7| 8| 9| 0
12| | 13|
10| 11| 5| 15

End result should be:

ALPHA|OMEGA|GAMMA|EPSILON|GREEK|BETA
1 | 2 | 3 |
| |
4 | 5 | 6 | 10|
11| 15
| 9| | 7|
8| 0
| 13| | 12|
|

Currently I have tried this:

array_file1 = []
array_file2 = []

row = 0
IO.foreach(“file1.txt” ) {
|line|
array_file1[row] = line.split("|")
row += 1
}

row = 0
IO.foreach(“file2” ) {
|line|
array_file2[row] = line.split("|")
row += 1
}
N = array_file1.length
array_file1.times(N) { |row|
if array_file1[row][1] == array_file2[row][2]
array_file2[row].each{
|col|
array_file1[row][array_file1i[row].length] = col
}
end
}

But I get Undefined Method

Logically, I want to
loop through row of array_file 1{
check to see if array_file1.OMEGA is equal to array_file2.OMEGA
loop through column
insert contents of array_file2 to end of array_file1
end loop
end loop

Any help would be greatly appreciated!


#2

lionbarrage wrote:

File 1
ALPHA|OMEGA|GAMMA
1 | 2 | 3
4| 5| 6

File 2
EPSILON|GREEK|OMEGA|BETA
7| 8| 9| 0
12| | 13|
10| 11| 5| 15

End result should be:

ALPHA|OMEGA|GAMMA|EPSILON|GREEK|BETA
1 | 2 | 3 |
| |
4 | 5 | 6 | 10|
11| 15
| 9| | 7|
8| 0
| 13| | 12|
|

Wow. What made you think you could tackle ascii art? And were you
actually satisfied with the result?


#3

End result should be:

ALPHA|OMEGA|GAMMA|EPSILON|GREEK|BETA
1 | 2 | 3 | | |
4 | 5 | 6 | 10 | 11 | 15
| 9 | | 7 | 8 | 0
| 13 | | 12 | |

I hoped I fixed your ASCII art the right way.

In understand that this represents named sets of integers that are to be
merged. Right?

The natural representation of that would be a hash containing sets.
There is a set class, but I use arrays here:

require ‘pp’

sets = Hash.new { | h, k | h[k] = [] } # hash that contains a new array
# for every new key
%w(file1.txt file2).each do | filename |
File.open(filename) do | f |
names = f.gets.chop.split(’|’)
f.each do | line |
names.zip(line.chop.split(’|’)).each do | name, value |
sets[name] << value
end
end
end
end

pp sets

This code does no tabular printing, treats the “integers” as strings,
without excluding empty strings and doubles. But that could easily be
fixed.

Probably I got it all wrong. :frowning:

mfg, simon … l


#4

On Feb 24, 8:58 pm, Simon K. removed_email_address@domain.invalid wrote:

EPSILON|GREEK|OMEGA|BETA
| 13 | | 12 | |

end
mfg, simon … l
Thanks for fixing my art, looked fine in my screen but I guess the
translation was off.

I’m not too familiar with hashes but the code you wrote seems to be
doing it. Thank you so much!!

How do i refer to a single element within a hash? Let’s say I want
11 for example. Would I do sets[“GREEK”][3]?

THANK YOU!


#5

On Feb 26, 4:51 am, Simon K. removed_email_address@domain.invalid wrote:

Simply by sets[‘GREEK’], but that single element is anarray.

Let’s say I want 11 for example. Would I do sets[“GREEK”][3]?

Yes, sets[‘GREEK’][1] should do.

mfg, simon … l

Thanks! I did:
sets.keys.each{|k|
print k, “|”
}
print “\n”
sets.values.each { |v|
pp v
}
which got me:

ALPHA|OMEGA|GAMMA|EPSILON|GREEK|BETA|
[“1”, “4”]
[“2”, “5”, “9”, “13”, “5”]
[“3”, nil]
[“7”, “12”, “10”]
[“8”, “”, “11”]
[“0”, nil, “1”]

Is there a format function which will remove “” and change , to | ?

Thanks tons!


#6

I’m not too familiar with hashes but the code you wrote seems to be
doing it. Thank you so much!!

Hashes are just like arrays, only the keys can be anything and not just
integers.

How do i refer to a single element within a hash?

Simply by sets[‘GREEK’], but that single element is an array.

Let’s say I want 11 for example. Would I do sets[“GREEK”][3]?

Yes, sets[‘GREEK’][1] should do.

mfg, simon … l


#7

| puts row.map { | v | if v then ‘%8s ’ % v else ’ ‘*9 end }.join(’|’)

Actually, since nil.to_s == “” you can do this simpler:

| puts row.map { | v | ‘%8s ’ % v }.join(’|’)

mfg, simon … l


#8

Thanks! I did:
sets.keys.each{|k|
print k, “|”
}
print “\n”

You could just do

puts set.keys.join(’|’)

To have the value output you specified in you original post, is a little
more complicated.

Is there a format function which will remove “” and change , to | ?

Don’t use pp for production use. Do your own formatting. Here’s my
updated script:

,----[ sets.rb ]
| #!/usr/bin/env ruby
|
| sets = Hash.new { | h, k | h[k] = [] } # hash that contains a new array
| # for every new key
| %w(file1.txt file2).each do | filename |
| File.open(filename) do | f |
| names = f.gets.chop.split(’|’)
| f.each do | line |
| names.zip(line.chop.split(’|’)).each do | name, value |
| sets[name] << value.to_i if value and value !~ /^\s*$/
| end
| end
| end
| end
|
| sets.values.each { | a | a.uniq! }
|
| puts sets.keys.map { | k | ‘%8s ’ % k }.join(’|’)
|
| rows = sets.values.map { | a | a.size }.max
|
| (1…rows).zip(*sets.values) do | row |
| row.shift
| puts row.map { | v | if v then ‘%8s ’ % v else ’ ‘*9 end }.join(’|’)
| end
`----

,----[ output ]
| GAMMA | OMEGA | GREEK | BETA | ALPHA | EPSILON
| 3 | 2 | 8 | 0 | 1 | 7
| 6 | 5 | 11 | 15 | 4 | 12
| | 9 | | | | 10
| | 13 | | | |
`----

If you don’t understand the code, please ask.

mfg, simon … l


#9

On Feb 28, 12:33 am, Simon K. removed_email_address@domain.invalid wrote:

puts set.keys.join(’|’)
| #!/usr/bin/env ruby
| end
| row.shift
`----

If you don’t understand the code, please ask.

mfg, simon … l

The output seems a little strange and I’m not sure why that is.

Output should be
ALPHA | OMEGA | GAMMA | EPSILON | GREEK | BETA
1 | 2 | 3 | | |
4 | 5 | 6 | 10 | 11 | 15
| 9 | | 7 | 8 | 0
| 13 | | 12 | |

instead it gets:
ALPHA | OMEGA | GAMMA | EPSILON | GREEK | BETA
1 | 2 | 3 | 7 | 8 | 0
4 | 5 | 6 | 12 | 11 | 15
| 9 | | 10 | |
| 13 | | | |

Please advise on what’s going on.

Thanks