inserting delimiters

[cam9269]

Hi Guys,

I need advise on how to format strings in a specific way.

I have this data extracted from the passwd file

user1,YNNNNNNNNNNNNNNNNNNN
user2,YNNNNNNYYNNNNNNNNNNN

field1 = username
field2 = user flags in the descriptions field

from the above format I wanted to create this output:

user1,Y,N,N,N,N,N,N,N,N,N,N,N,N,N,N,N,N,N,N
user2,Y,N,N,N,N,N,N,Y,Y,N,N,N,N,N,N,N,N,N,N

TIA!

[Hein van den Heuvel · Accepted solution]

$ perl -lpe'($u,$f)=split /\W/; $_=join q(,),$u,split(//,$f)'

-lpe = loop trhough input and print $_ with newline

First split on non-Word (The , and the new-line) saving username in $u, flags in $f.

The re-join with commas, that username, and the flags where those are re-split on 'nothing'.

Enjoy,
Hein.

[Dennis Handly]

I you have exactly 20 and you don't want to write a script to break them up, you can use sed:
================================================
sed -e 's/\(.*,\)\(.\)\(.\)\(.\)\(.\)\(.\)\(.\)\(.\)\(.\)/\1\2,\3,\4,\5,\6,\7,\8,\9,/' \
-e 's/\(.*,.,.,.,.,.,.,.,.,\)\(.\)\(.\)\(.\)\(.\)\(.\)\(.\)\(.\)\(.\)/\1\2,\3,\4,\5,\6,\7,\8,\9,/' \
-e 's/\(.*,.,.,.,.,.,.,.,.,.,.,.,.,.,.,.,.,\)\(.\)\(.\)\(.\)\(.\)/\1\2,\3,\4,\5/'

[OFC_EDM]

Here's one example at an easier level.
Disadvantage is it calls multiple sed statements. But it's easier to understand if you're just starting out.

cat testdata
user1,YNNNNNNNNNNNNNNNNNNN
user2,YNNNNNNYYNNNNNNNNNNN

cat testdata | tr "," " " | sed -e 's/Y/Y /g' | sed -e 's/N/N /g' | sed -e 's/ /,/g' | sed -e 's/$,//g'

Output
user1,Y,N,N,N,N,N,N,N,N,N,N,N,N,N,N,N,N,N,N,N
user2,Y,N,N,N,N,N,N,Y,Y,N,N,N,N,N,N,N,N,N,N,N

Approach
Decided a space will be the final Field delimeter.
So replaced that first comma with a space
tr "," " "
Then put a space beside all Y's and N's
sed -e 's/Y/Y /g' | sed -e 's/N/N /g'
Then replaced all spaces with a comma
sed -e 's/ /,/g'
And then finally removing the comma that would be left at the end of the string from the previous step
sed -e 's/,$//g'

[cam9269]

Well done guys! Many, many thanks for the prompt replies. I really need to get my scripting level up more.

These options are superb!

Thanks again!

[cam9269]

Thanks very much for the explanations KU. You deserve more that 10pts for this. :)

[cam9269]

Also to Hein, though I'm a newbie's newbie when it comes to perl scripting. Appreciate it! it'll be my first 'hard' script to understand with perl.

[Steven Schweda]

> Disadvantage is it calls multiple sed
> statements.

It doesn't need to. Multiple "-e" options
should do the job with one "sed".

Of these two:

> [...] 's/$,//g'
> [...] 's/,$//g'

the second one works better. And is "tr"
really needed?

bash$ echo 'user1,YNNNNNNNNN' | \
sed -e 's/,/ /' -e 's/Y/Y /g' -e 's/N/N /g' -e 's/ /,/g' -e 's/,$//g'
user1,Y,N,N,N,N,N,N,N,N,N

[Dennis Handly]

>Thanks very much for the explanations

I can explain my regular expressions:
1) It captures everything up to the first comma and puts it back.
2) It then captures 8 characters and puts each back followed by a ",".
3) Since \# only works for 1..9, it does 8 more, after first accepting the first 8.
4) Then it does the final 4 after accepting the first 16.

[Steven Schweda]

> [...] Closing thread now

Ha! As if that could stop me...

bash$ echo 'user1,YNNNNNNNNN' | \
sed -e 's/,/ /' -e 's/\([NY]\)/\1 /g' -e 's/ /,/g' -e 's/,$//g'
user1,Y,N,N,N,N,N,N,N,N,N

[Hein van den Heuvel]

My solution is best explained by taking out all shortcuts:

$ perl -lpe'($u,$f)=split /\W/; $_=join q(,),$u,split(//,$f)'

Really is...

while ($line = ) {
($user, $flags) = split (/\W/, $line);
@letters = split(//, $flags);
$new_line = join ',' , $user, @letters;
print $new_line, "\n";
}

Hein.

[cam9269]

appreciate your enthusiasm Steven! I picked up on your advice :)
Thanks for the notes Hein! Will likely to play and consider it in the code too

Cheers!

[Dennis Handly]

>Steven: As if that could stop me...
>echo 'user1,YNNNNNNNNN' | \
sed -e 's/,/ /' -e 's/\([NY]\)/\1 /g' -e 's/ /,/g' -e 's/,$//g'

It is obvious this isn't going to work if the user name is like "YESNO".

I'm also not sure why you want to change to spaces then back?
Note: the "g" in 's/,$//g' is useless.

[cam9269]

i really, really appreciate all the inputs! :)

[Dennis Handly]

You can also use awk. Unfortunately I can't get split to work there with an empty RE.
awk -F, '
{
printf $1 ","
for (i=1; i < 20; ++i)
printf substr($2,i,1) ","
print substr($2,20,1)
} '