String manipulation: cut, insert, column editing

Ruby
1

Hi all,

Is it possible to use ruby like awk, sed or cut in unix to editing
strings?

Let say I have to write INSERT query like this:

This is the first (1°) item.
This is the second (2°) item.
This is the third (3°) item.
…

In one file I have the word-number (first, second, third) and in another
file I have the real number (1°, 2°, 3°) of the item, both on each line.

Of course, I don’t want to really write it, so how can I “edit” the
number of the item dinamically? I’ve tried with regex, but I haven’t
found a solution…

I think that with some text editors maybe it’s possible to do that, but
I would like to know if with ruby the result can be achieved easier.

Let me know.

Thanks.

Best regards.

2

Toki T. wrote:

Let say I have to write INSERT query like this:

This is the first (1°) item.
This is the second (2°) item.
This is the third (3°) item.
…

I don’t think this would be the best solution, but you could map 1 =>
“first”… and then use regex to identify the number and get its mapped
value. Problem is that it runs one way and limited.

3

On Aug 12, 3:09 pm, Toki T. [email protected] wrote:

…

In one file I have the word-number (first, second, third) and in another
file I have the real number (1°, 2°, 3°) of the item, both on each line.

Here’s some Ruby code that may do what you’re interested in:

====

d1 = open(“f1.txt”) do |f|
f.readlines.map { |line| line.chomp }
end

d2 = open(“f2.txt”) do |f|
f.readlines.map { |line| line.chomp }
end

d3 = [d1, d2].transpose

p d1, d2, d3 # just so you can see what’s happened so
far

d3.each do |str1, str2|
puts “This is the #{str1} (#{str2}) item.”
end

====

That’s assuming f1.txt contains “first”, “second”, etc., one per line
and that f2.txt contains “1st”, “2nd”, etc., one per line.

Eric

====

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4

Eric I. wrote:

Here’s some Ruby code that may do what you’re interested in:

====

d1 = open(“f1.txt”) do |f|
f.readlines.map { |line| line.chomp }
end

d2 = open(“f2.txt”) do |f|
f.readlines.map { |line| line.chomp }
end

d3 = [d1, d2].transpose

p d1, d2, d3 # just so you can see what’s happened so
far

d3.each do |str1, str2|
puts “This is the #{str1} (#{str2}) item.”
end

====

That’s assuming f1.txt contains “first”, “second”, etc., one per line
and that f2.txt contains “1st”, “2nd”, etc., one per line.

Eric

====

Thanks a lot for the code, it works great and it’s really clear.

Best regards.

5

2008/8/12 Toki T. [email protected]:

Is it possible to use ruby like awk, sed or cut in unix to editing
strings?

These are quite different tools but yes, you can use Ruby like them
most of the time. Please also have a look at command line parameters
of the Ruby interpreter (ruby -h).

Let say I have to write INSERT query like this:

This is the first (1°) item.
This is the second (2°) item.
This is the third (3°) item.
…

This does not look like an SQL INSERT statement, what is it?

In one file I have the word-number (first, second, third) and in another
file I have the real number (1°, 2°, 3°) of the item, both on each line.

Not sure what exactly you are trying to do. For the loading part
here’s another variant:

h = {}

File.open “f1.txt” do |io1|
File.open “f2.txt” do |io2|
io1.zip io2 do |k,v|
h[k.chomp] = v.chomp
end
end
end

p h

Of course, I don’t want to really write it, so how can I “edit” the
number of the item dinamically? I’ve tried with regex, but I haven’t
found a solution…

I think that with some text editors maybe it’s possible to do that, but
I would like to know if with ruby the result can be achieved easier.

Well, if you tell us what exactly you are trying to achieve. At least
to me it’s not fully clear.

Kind regards

robert

6

Hi Eric –

On Wed, 13 Aug 2008, Eric I. wrote:

This is the third (3°) item.
f.readlines.map { |line| line.chomp }
end

You can even skip the readlines and just map the IO handle:

f.map {|line| line.chomp }

David